Collection Guidelines for TACE

COLLECTION GUIDELINESFOR -

Collecting Animal Registration Details

Important information for the calculation of TransTasman Angus Cattle Evaluation (TACE) EBVs is collected when animals are registered with Angus Australia.

• Pedigree: the sire and dam that is recorded for an animal has a large impact on the EBVs that are calculated for not only the animal, but its progeny and grand progeny. It is essential that the sire and dam specified for an animal is accurate. If there is any doubt as to who the correct sire and dam is, DNA parentage verification should be conducted.

• Sex: sex is used to form contemporary groups within the TACE analysis, with only the performance of calves of the same sex (i.e. males, females) being directly compared together. Care should be taken to ensure that the sex recorded for each animal is accurate, and any errors that are identified immediately corrected.

TACE can calculate EBVs for animals without pedigree information (e.g. base animals), however the EBVs will be of lower accuracy.

• Birth Date: birth date is used within the TACE analysis to adjust for differences in the age of the animals at the time of measurement, and to form contemporary groups. Animals should be checked daily during calving and the birth date of each calf recorded.

While not submitted in associated with animal registrations, it is important to clearly identify any animals that have been castrated when submitting performance information to Angus Australia.

• Birth Number: birth number is used to form contemporary groups within the TACE analysis, with only the performance of calves of the same birth number (i.e. singles, twins, triplets) being directly compared together. The birth number for all calves should be accurately recorded.

Management groups should be submitted in association with the performance for any calves from a multiple birth who are subsequently raised as a single calf in order to clearly differentiate them from calves who are raised as multiples.

• Breed: breed is used within the TACE analysis to adjust for any differences in the performance of animals that can be attributed to heterosis. While breed is automatically assigned to the majority of animals based on the breed information that is recorded on the Angus Australia database for their sire and dam, care should be taken to accurately record breed information when recording “base” (i.e. animals with an unknown parent) or “overseas” animals.

The breed information that is recorded for “base” or “overseas” animals is used to calculate the breed of any descendants that are recorded with Angus Australia, which will subsequently influence how the performance of these descendants is analysed within TACE.

• Mating Type: mating type is used to form contemporary groups within TACE, with the performance of calves from natural and AI matings analysed in a separate contemporary group to the performance of calves bred in an embryo transfer program. Care should be taken to ensure the mating type recorded for each animal is accurate.

• Recipient Dam Details: the breed and birth year of the recipient dam is used within TACE to account for any differences in the performance of embryo transfer calves that can be attributed to differences in the maternal contribution from the recipient. Care should be taken to ensure recipient dam information, particularly breed and birth year is accurately recorded.

If recipient dam information is not recorded, the performance of embryo transfer calves will not be analysed within the TACE analysis.

• Country of Origin: the country of origin is used to assist with the calculation of “starting EBVs” for base or overseas animals. The country of origin should be accurately recorded for all base or overseas animals.

• Overseas Society Ident: the TACE analysis combines information recorded with both the Angus Australia and Angus New Zealand breed organisations, while also incorporating EPD information from a number of North American genetic evaluations. When recording overseas animals with Angus Australia, care should be taken to ensure the ident of the animal with the overseas breed organisation is recorded on the Angus Australia database.

If the overseas society ident is not accurately recorded for an animal, information for animals recorded with both Angus Australia and New Zealand Angus may not be combined appropriately, and EPD information may not be used to appropriately assign the “starting” EBVs for animals imported from North America.

Collecting Calving Difficulty Scores

Calving difficulty should be measured at or shortly following birth by visually scoring the degree of calving difficulty on the following scale of 1 - 6.

If females are regularly checked during calving (e.g. on a daily basis), it is reasonable to assume that a calf who has been born without assistance between visits can be scored as unassisted (no difficulty) even though the calving was not observed.

Calving difficulty scores, in association with birth weight and gestation length information, are used to calculate Calving Ease Direct and Calving Ease Daughters EBVs within the TransTasman Angus Cattle Evaluation (TACE). Score Code Description

1 Unassisted Cow calved unassisted / No difficulty

2 Easy Pull One person without mechanical assistance

Two people without mechanical assistance

3 Hard Pull

One person with mechanical assistance

4 Surgical Assistance Veterinary intervention required

5 Mal-presentation e.g. Breech

6 Elective surgical

Surgical removal of calf before the cow has the opportunity to calve

* Note that a blank score will not be interpreted as “unassisted”. Instead, it indicates that calving difficulty was not scored

Blank or 0 is interpreted as no score recorded rather than “no difficulty”.

• Calving difficulty scores should be recorded for the whole calf drop. Collecting “occasional” scores, or only collecting calving difficulty scores for a subset of calves is of no value and can lead to the calculation of biased Calving Ease EBVs.

• Record calving difficulty scores for all calves rather than just difficult or easy births. Recording calving difficulty scores for dead calves is particularly important.

• There needs to be some level of calving difficulty in the herd for the scores to be used effectively in the TACE analysis. That is, simply scoring all births in a herd with a calving difficulty score of [1] will not identify any genetic differences in ease of calving.

• A birth management group should be recorded if there are different treatments of the females prior to calving that may affect calving difficulty. For example, where one group of cows have had different feed availability, or where the level of calving difficulty has been affected by special circumstances (e.g. premature calves, the dam was sick etc.)

• A calving difficulty score of [2] should be allocated where calves are born unassisted but some degree of calving difficulty is evident. For example, stillborn calves where the head is swollen and it is obvious the calf has died as a result of a difficult calving.

• When calculating the Calving Ease EBVs, calving difficulty scores of [3] and [4] are grouped together. Calving difficulty scores [5] & [6] are excluded from the TACE analysis as the problems are considered non-genetic in origin.

• In addition to calving difficulty scores, birth weight and gestation length information is also included in the calculation of Calving Ease EBVs. Breeders wishing to optimise the accuracy of their Calving Ease EBVs should also consider collecting this information and submitting it to the TransTasman Angus Cattle Evaluation.

Collecting Gestation Length

Gestation length information is used to calculate Gestation Length EBVs within the TransTasman Angus Cattle Evaluation (TACE).

TACE will calculate Gestation Length EBVs based on the joining and birth records for calves conceived by either artificial insemination (AI) or hand mating.

Information needed for the calculation of Gestation Length EBVs includes:

the joining (or AI) date of any calves conceived by AI or hand mating the date of birth for each calf

Gestation length for each calf does not need to be recorded. TACE will calculate the gestation length from the joining date and date of birth information that is submitted.

• Gestation length information should only be submitted for calves conceived by either AI or hand mating. Hand mating refers to situations where the female is given limited exposure to a bull (e.g. in a yard), mating occurs, and then the bull is removed.

• No information from natural paddock matings is used in the calculation of Gestation Length EBVs. Although some natural matings may be observed, they are not currently used in the calculation of gestation length as there is no guarantee that the observed mating is the one that successfully results in the conception of the calf.

• Gestation length information should be recorded for all calves conceived via AI or hand mating in a calf drop. Only submitting gestation length information for a subset of calves is of no value and may result in biased Gestation Length EBVs.

• A birth management group should be recorded if there are different treatments of the females prior to calving that may affect gestation length. For example, where one group of cows have had different feed availability. Likewise, a separate birth management group should be assigned for any premature calves, or calves whose gestation length has been affected by special circumstances. (e.g. the dam was sick).

• Gestation length information is currently excluded from the TACE analysis if (a) the calf is an embryo transfer calf, (b) the calf is a twin, (c) only one animal is represented in a contemporary group, or (d) more than 2/3 of animals in a contemporary group have the same gestation length.

Collecting Birth Weights

The weights of calves taken shortly following birth are used to calculate Birth Weight EBVs within the TransTasman Angus Cattle Evaluation (TACE).

How do you record birth weights?

Many different methods are used to collect calf birth weight. These range from using bathroom scales through to the use of commercially available calf weighing cradles that can be attached to the tray of a utility or the front of a four wheel motorbike.

A few examples of birth weighing devices include:

• hand held weigh scales

• calf cradle mounted on a quad bike or trailer

• calf crate suspended from a utility

When should calves be weighed?

The weight of a calf fluctuates throughout the first week of its life. It is therefore important to weigh calves as close to birth as possible.

When recording the birth weight of calves, it is important that accurate birth weights are collected using appropriate weighing scales.

Ideally, birth weight should be recorded within 24 hours of birth, and no greater than 48 hours after birth.

Unacceptable methods

Birth weights collected using the following methods are not appropriate for submission to TACE:

Use of coronet band tapes ? ? ?

Visual estimates or “guesses”

Use of chest or girth tapes

• Birth weights should be recorded for the whole calf drop. Collecting “occasional” measurements, or only collecting birth weights for a subset of calves is of no value and can actually be misleading.

• Recording birth weight for dead calves is particularly important.

• A birth management group should be recorded if there are different treatments of the females prior to calving that may affect birth weight.

• For example, where one group of cows have had different feed availability. A separate birth management group should also be assigned if the weight of the calf has been affected by special circumstances (e.g. premature calves, the dam was sick etc.).

• Some breeders have been injured by protective cows while weighing calves. It is important to take due care when collecting this information. A number of agricultural supply stores are now offering calf catching equipment that is designed to improve safety.

Collecting 200 Day Weights

Live weights taken on calves when the average age of the contemporary group is between 80 and 300 days of age are used to calculate both 200 Day Growth EBVs and Milk EBVs within the TransTasman Angus Cattle Evaluation (TACE).

Recording 200 day weights

All weights should be recorded using appropriate (and accurate) scales. Do not guess/estimate weight or use measuring tapes to calculate weight. Either weigh the calves using appropriate scales or don’t record weights.

Weights should be recorded to the nearest kilogram.

When should 200 day weights be collected?

The 200 day weight for a calf needs to be recorded when the average age of their contemporary group is between 80 and 300 days of age.

Within this age range, a date should be chosen that fits in with normal, routine management practices (e.g. weaning) and is reasonably close to when the average age of the group of calves is 200 days of age. TACE provides suggested weigh dates to assist you when making this decision.

If particularly looking to optimise the quality of Milk EBVs, 200 day weights should be collected at or before weaning. Likewise, if a significant number of cows have weaned calves naturally (i.e. have “dried off”) before the calves are “physically” weaned, then it may be beneficial to consider taking an early weight on all calves.

Calves do not need to be weighed when they are all individually 200 days of age on the day of weighing, but rather the whole contemporary group weighed when the average age of the group is approximately 200 days (i.e. 6 – 7 months).

• 200 day weights should be collected for all animals in a contemporary group. Only recording 200 day weights for a subset of calves is of no value and can lead to biased 200 Day Growth EBVs.

• All calves in a contemporary group should be weighed on the same day. TACE will not directly compare the 200 day weights of calves that have been weighed on different days. Similarly, any subsequent performance for calves weighed on different days at 200 days will also be analysed in separate groups (e.g. 400 day weights, ultrasound scanning measurements).

• 200 day weights should be collected when animals are in as large a group as possible. Consequently, try to collect 200 day weights before any of the calves in a management group are treated differently. For example, before some bulls are castrated at marking or the show team is separated from the rest of the contemporary group.

• There is no requirement to curfew or “empty out” calves prior to weighing for TACE. Care however should be taken to ensure that the weights of some calves are not unduly affected by significant differences in the length of time off feed and water prior to weighing.

• A management group should be recorded for any animals that have been treated differently or exposed to significant non-genetic influences prior to measurement that may affect their 200 day weight. For example, the 200 day weights of calves given a supplement should be recorded in a different management group to those without a supplement. Consideration should also be given to variations in pasture quality, stocking rates, water quality, animal health, injury etc.

• TACE can analyse two 200 day weights on each animal. Generally speaking, it is only necessary to record one weight, however in some circumstances, recording more than one weight will improve the accuracy of the 200 Day Growth EBVs. For example, when early weaning is practiced, it may be beneficial to take an early weight at the time of weaning, and a subsequent weight when calves have reached 200 days of age.

• Consideration should be given to also collecting docility scores, calf DNA samples, and mature cow weights in association with the collection of 200 day weight measurements.

Weigh when the average age of the group, rather than each individual animal, is 200 days.

Collecting 400 Day Weights

Live weights taken on animals when the average age of the contemporary group is between 301 and 500 days of age are used to calculate 400 Day Weight EBVs within the TransTasman Angus Cattle Evaluation (TACE).

Recording 400 day weights

All weights should be recorded using appropriate (and accurate) scales. Do not guess/estimate weight or use measuring tapes to calculate weight. Either weigh the animals using appropriate scales or don't record weights. Weights should be recorded to the nearest kilogram.

When should 400 day weights be collected?

The 400 day weight for an animal needs to be recorded when the average age of their contemporary group is between 301 and 500 days of age.

Within this age range, a date should be chosen that fits in with normal, routine management practices and is reasonably close to when the average age of the group of animals is 400 days of age. TACE provides suggested weigh dates to assist you when making this decision.

Animals do not need to be weighed when they are all individually 400 days of age on the day of weighing, but rather the whole contemporary group weighed when the average age of the group is approximately 400 days (i.e. 13 – 14 months).

Use appropriate and accurate scales

• 400 day weights should be collected for all animals in a contemporary group. Only recording 400 day weights for a subset of animals is of no value and can lead to biased 400 Day Weight EBVs.

• All animals in a contemporary group should be weighed on the same day. TACE will not directly compare the 400 day weights of animals that have been weighed on different days. Similarly, any subsequent performance for animals weighed on different days at 400 days will also be analysed in separate groups (e.g. 600 day weights, ultrasound scanning measurements).

• 400 day weights should be collected when animals are in as large a group as possible. Consequently, try to collect 400 day weights before any of the animals in a management group are treated differently. For example, before some bulls are joined, or females separated into different groups for joining.

• There is no requirement to curfew or “empty out” animals prior to weighing for TACE. Care however should be taken to ensure that the weights of some animals are not unduly affected by significant differences in the length of time off feed and water prior to weighing.

• A management group should be recorded for any animals that have been treated differently or exposed to significant non-genetic influences since weighing at 200 days that may affect their 400 day weight. For example, the 400 day weights of animals given a supplement should be recorded in a different management group to those without a supplement. Consideration should also be given to variations in pasture quality, stocking rates, water quality, animal health, injury etc.

• TACE can analyse two 400 day weights on each animal. Generally speaking, it is only necessary to record one weight, however in some circumstances, recording more than one weight will improve the accuracy of the 400 Day Weight EBVs.

• Consideration should be given to also collecting live animal ultrasound scanning and scrotal circumference measurements in association with the collection of 400 day weight information.

Collecting 600 Day Weights

Live weights taken on animals when the average age of the contemporary group is between 501 and 900 days of age are used to calculate 600 Day Weight EBVs within the TransTasman Angus Cattle Evaluation (TACE).

Recording 600 day weights

All weights should be recorded using appropriate (and accurate) scales. Do not guess/estimate weight or use measuring tapes to calculate weight. Either weigh the animals using appropriate scales or don’t record weights. Weights should be recorded to the nearest kilogram.

When should 600 day weights be collected?

The 600 day weight for an animal needs to be recorded when the average age of their contemporary group is between 501 and 900 days of age.

Within this age range, a date should be chosen that fits in with normal, routine management practices (e.g. pregnancy testing heifers) and is reasonably close to when the average age of the group of animals is 600 days of age. TACE provides suggested weigh dates to assist you when making this decision.

Animals do not need to be weighed when they are all individually 600 days of age on the day of weighing, but rather the whole contemporary group weighed when the average age of the group is approximately 600 days (i.e. 20 months).

Important considerations when collecting 600 day weights for heifers

Recording 600 day weights on heifers that are in the later stages of pregnancy can cause significant bias to the 600 Day Weight EBVs that are calculated due to variation in live weight being incorrectly attributed to differences in growth genetics.

The additional weight at each stage of pregnancy in an Angus heifer resulting from a 39kg calf (at birth) is outlined in the table below.

• 600 day weights should be collected for all animals in a contemporary group. Only recording 600 day weights for a subset of animals is of no value and can lead to biased 600 Day Weight EBVs.

• All animals in a contemporary group should be weighed on the same day. TACE will not directly compare the 600 day weights of animals that have been weighed on different days.

• 600 day weights should be collected when animals are in as large a group as possible. Consequently, try to collect 600 day weights before any of the animals in a management group are treated differently.

• If selling bulls at 18 months of age, consideration can be given to collecting an early 600 day weight before these bulls have been sold. Animals can be weighed for 600 Day Weight EBVs from 501 days of age onwards (ie. 16-17 months).

• There is no requirement to curfew or “empty out” animals prior to weighing for TACE. Care however should be taken to ensure that the weights of some animals are not unduly affected by significant differences in the length of time off feed and water prior to weighing.

• A management group should be recorded for any animals that have been treated differently or exposed to significant non-genetic influences since weighing at 400 days that may affect their 600 day weight. For example, the 600 day weights of animals given a supplement should be recorded in a different management group to those without a supplement. Consideration should also be given to variations in pasture quality, stocking rates, water quality, animal health, injury etc.

• TACE can analyse two 600 day weights on each animal. Generally speaking, it is only necessary to record one weight, however in some circumstances, recording more than one weight will improve the accuracy of the 600 Day Weight EBVs.

If heifers are being calved down at 2 years of age, as is usually the case in Angus breeding enterprises, consideration can be given to collecting 600 day weights for heifers at an earlier age (e.g. 550 days of age, or commonly pregnancy testing) when the effect of pregnancy status on weight is minimal.

• Consideration should be given to also collecting live animal ultrasound scanning, scrotal circumference, and structural soundness measurements in association with the collection of 600 day weight information.

Collecting Mature Cow Weights

Weights recorded for cows at the same time as the 200 day weights are recorded for their calves are used to calculate Mature Cow Weight EBVs within the TransTasman Angus Cattle Evaluation (TACE).

Recording mature cow weight data

Mature cow weights should be recorded using appropriate (and accurate) scales. Do not guess/estimate weight or use measuring tapes to calculate weight. Either weigh the cows using appropriate scales or don’t record weights. Mature cow weights should be recorded to the nearest kilogram.

When should mature cow weights be collected?

The mature weight for a cow needs to be recorded at the same time as the 200 day weight is taken for its calf.

TACE will only analyse the weight of a mature cow if the cow has a calf with a weight recorded within 2 weeks of when the mature weight was taken and further, the calf was between 80 – 300 days of age when it was weighed. There is no need to weigh cows that have not raised a calf to 200 days. Weights on these cows will not be analysed with the TACE genetic evaluation.

• TACE can analyse up to 4 mature weights for each cow. Therefore, all cows with a calf at 200 days should be weighed each year. Do not try to “guess” whether a cow has had 4 weights taken previously – the TACE analysis will sort it out for you.

• Management group information should be specified for any cows or groups of cows that have been managed differently in previous years where the difference in management is still considerably affecting their weight relative to other cows born in the same year. For example, cows that may not have weaned a calf in the previous year, cows that have previously been part of the show team but are now part of the main herd, or in situations where cows of the same age were calved down at different ages (e.g. 2, 2.5 and 3 years of age).

• Mature weights should be recorded for all females in a mob on the same day. TACE will not directly compare mature weights for cows that have been collected on different days.

• Management group information should be recorded for any cows or group of cows that have been treated differently or exposed to significant non-genetic influences prior to weighing that may affect their weight.

• Additional performance recording information can be collected as part of current and future research projects. This information is not currently included in the TACE analysis, however this information may be used in the future when calculating EBVs. Refer to the relevant collection guidelines for submitting performance information as part of the project.

Management groups

Management groups work slightly differently for mature cow weights. If no management group information is defined for a set of mature cow weights, the TACE analysis will use the management groups submitted with the 200 day weights of their calves to sub-group the weights of the cows. Therefore, if management group information has been correctly recorded with the 200 day weight performance for the calves, then a different management group only needs to be assigned to a cow that has experienced an effect on her weight that is different to that experienced by her calf. For example, if the cow was injured or sick.

If both the mature cow weights and the 200 day weights for their calves are submitted without management group information, the TACE analysis will assume all cows and calves have been run under similar management conditions.

IMPORTANT CONSIDERATIONS

TACE will only analyse mature weights for cows that are between 2.4 – 10.7 years of age (870 –3900 days) at weighing.

TACE will only analyse mature weight information for a cow if the first valid mature weight for the cow has been taken before the animal is 6 years of age (2200 days). If not, then none of the mature weights for the cow will be analysed.

Collecting Scrotal Circumference Measurements

Scrotal circumference measurements taken on bulls between 300 and 700 days of age are used to calculate Scrotal Size EBVs within the TransTasman Angus Cattle Evaluation (TACE)

Recording scrotal circumference measurements

Scrotal circumference measurements should be recorded by pulling the testes firmly down into the lower part of the scrotum and placing a measuring tape around the widest point (as per the photo below). Scrotal circumference measurements can be taken by anyone. They do not need to be taken by an accredited technician.

When measuring scrotal circumference, remember;

1

2 3

4

While measuring techniques vary slightly, it is important to use a consistent technique for the whole group of bulls.

The tension applied to the measuring tape should be just sufficient to cause a slight indentation in the skin of the scrotum.

Avoid placing the thumb of the hand holding the neck of the scrotum between the cords. This will cause separation of the testes and an inaccurate measurement.

Appropriate (and accurate) measuring tapes should be used to collect scrotal circumference measurements.

A variety of scrotal circumference measuring devices are commercially available from agricultural supply stores or organisations such as the Australian Cattle Veterinarians. Metal scrotal measuring tapes are more reliable than cloth tapes as they are not prone to stretching.

When should scrotal circumference measurements be collected?

TACE can analyse scrotal circumference information from bulls that are between 300 – 700 days of age when measured. Subsequently, it is essential that scrotal circumference information is recorded when bulls are within this age range.

It is recommended that scrotal circumference is measured when bulls are reaching puberty, which will vary according to seasonal conditions and the maturity pattern of the animals being measured. In the majority of cases, the optimum time to record scrotal circumference measurements for TACE is when bulls are being weighed at 400 days.

• While more than one scrotal circumference measurement can be recorded for an individual animal, TACE is only analysing the first measurement for each bull at this stage. Subsequently, it is only necessary to record one scrotal circumference measurement on each bull for TACE.

• Scrotal circumference measurements should be collected for all bulls in a mob. Only recording scrotal circumference measurements for a subset of bulls is of no value and can lead to biased Scrotal Size EBVs.

• A management group should be recorded for any bulls or group of bulls that have been treated differently or exposed to significant non-genetic influences prior to measurement that may affect their scrotal circumference. For example, the scrotal circumference measurements for bulls given a supplement should be recorded in a different management group to those without a supplement. Consideration should also be given to variations in pasture quality, stocking rates, water quality, etc.

• A management group should be recorded for any bulls that have been joined prior to measurement.

• Scrotal circumference measurements should be recorded for all bulls in a mob on the same day. TACE will not directly compare scrotal circumference measurements collected on different days.

• Scrotal circumference measurements should be collected when bulls are in as large a group as possible. Consequently, try to collect scrotal circumference measurements before any of the bulls in a management group are treated differently. For example, before some bulls are joined or bulls are separated into smaller groups for ease of management.

Scrotal circumference should be recorded in centimetres (to one decimal place).

Measure the testes at their widest point

Collecting Days to Calving Information

Joining details of heifers and mature cows mated in natural paddock joining programs are used to calculate Days to Calving EBVs.

What to collect?

Breeders interested in the Days to Calving EBV need to record all ‘events’ associated with the natural joining of their females from the start of the mating period in each breeding season through to when the subsequent calves are born. This includes those females that have only been joined naturally within a breeding season - not those that have been included in artificial insemination/ embryo transfer programs or artificially induced to cycle prior to joining with the bull outside of such programs. Broadly, the information to be collected should include:

1 2 3

Joining details of ALL females naturally mated within the herd.

Details of ALL females removed from the herd, particularly those present at joining that were no longer within the herd by the time of the subsequent calving.

Details of ALL calves (dead or alive) that are born as a result of these joinings.

While not currently included in the Days to Calving analysis, research is now underway to determine whether details from artificial insemination (AI) and embryo transfer (ET) programs could be utilised by TACE (TransTasman Angus Cattle Evaluation).

Joining details

Record each natural joining event to which a female (cow or heifer) is exposed within the breeding season whether this was the successful joining or not. For situations where females are joined to several bulls in a mating season, record all joinings for the female, not just the first or successful joining.

For each natural joining event within the breeding season, record the bull the female was joined to, the date she was joined (‘bull in’ date) and the date the bull was removed (‘bull out’ date). Knowing the end of the joining period is important in analysing the Days to Calving trait.

Record management group information to identify any cow/s within a joining group whose fertility may have been affected either prior to or during the joining program due to non-genetic factors. e.g. significantly different nutrition, sickness, injury. A maximum of three characters (letters and/or numbers) can be used to describe each management group.

Calf details

All calves that are born as a result of the joinings need to be recorded with Angus Australia. Not recording all calves (including dead calves) will bias the Days to Calving EBVs that are calculated.

Female disposal

Record the date and reason for any female removed from the herd, particularly those present at the start of joining that are no longer within the herd by the time of the subsequent calving. The fate/disposal code information is critical to the Days to Calving analysis and is used to determine whether females that have a joining record but no subsequent calf should be penalised for being “culled for infertility” or not penalised because they were culled for other reasons e.g. structure, performance etc. In the future, this information may also be used as part of the calculation of a Female Longevity EBV.

The codes to be used to record a female fate/disposal event are as follows:

Culled or sold Code

A Cast for age

B Sold surplus breeding female - but not code J or F

C Calving incident

D Disease

E Eyes (e.g. pesti, eye cancer, etc)

F Not in calf (i.e. failed preg test or did not calve)

G Genetic condition (e.g. genetic carrier)

H Horns

J Cull unjoined heifer surplus to requirements

K Coat Type

P Poor performance (e.g. poor milking, low body condition, etc)

Q Appearance (type, colour, markings, Society standards, etc)

R Reproduction abnormality (e.g. freemartin, mal-formed uterus, pelvic area)

S Structural problem (e.g. feet, legs, navel, etc)

T Poor temperament

U Udder or teat problems

V Poor EBVs

W Calved but failed to rear calf to weaning

X Susceptible to parasites (ticks, buffalo fly, worms, etc

Died or missing

Code Description

C Calving incident (e.g. dystocia, prolapsed)

D Disease (e.g. pesti, bloat, 3 day, etc)

M Missing assumed dead

X Parasites (ticks, buffalo fly, worms, etc)

Y Unknown cause

Z Accident (e.g. injury, drowned, poisoned, etc)

The disposal codes submitted for the purposes of removing animals from the female inventory are not currently utilised in the calculation of Days to Calving EBVs, and likewise disposal codes submitted for the calculation of Days to Calving EBVs will not remove animals from the female inventory. Consequently, disposal codes need to be submitted in association with days to calving joining information, even if they have already been submitted in association with female inventory.

Pregnancy test results

Optionally, where pregnancy test results are available, record the date and result of the test for each female joined. This information is not currently included in the Days to Calving analysis, however it may be utilised in the future to either enhance the calculation of Days to Calving EBVs, or for the calculation of other female fertility EBVs.

Pregnancy test results should be reported as:

N = Not pregnant

P = Pregnant

A number between 3-20 (i.e. the number of weeks pregnant as advised by a qualified technician. )

Where the fetus is over 20 weeks old, a ‘P’ should be used.

The joinings or fate/disposal information that is submitted in association with calf registrations or female inventory is not included in the Days to Calving analysis.

• Collect joining details for ALL cows in the recorded herd to accurately reflect the cow fertility in the herd. Simply recording those cows that have a calf or those cows that remain on inventory in the next year is not adequate.

• Collect details for all maiden heifers joined – not just the ones that calve or are added to inventory. Information on maiden heifers is very important as many herds cull heifers that do not conceive in the first year of joining. The heifers that do not calve supply as much information to the analysis as those that do calve.

• Record the details of all joining events in which the female was involved even if the joining was unsuccessful. For situations where females are joined to several bulls in a mating season, record all joinings for each cow and heifer within the joining period, not just the first or successful joining.

• Accurately recording the fate/disposal codes of all females that leave the herd is extremely important. In the Days to Calving analysis, this fate/disposal code information is used to determine whether a female should be penalised for being “culled for infertility” or not penalised because she was culled for other reasons (e.g. structure, performance etc.)

• Joining details for females that have been joined to multiple sire groups (rather than a single sire) should also be recorded. In this scenario, the sire ident that is specified should be the multiple sire ident, rather than the ident of the individual sire that resulted in the calf. Similarly, joining details for females mated to sires not recorded with Angus Australia (e.g. unregistered sires, sires of another breed) should also be submitted.

The code for natural joining events is N (Natural/Paddock mating)

• Herds with either a very wide calving spread (e.g. cows joined all year around), several calvings each year (e.g. an autumn, winter and spring calving), or who have a high proportion of artificial breeding may have difficulty collecting joining information that is useful for the calculation of Days to Calving EBVs. Herds in such situations should contact staff at Angus Australia for further advice.

Collecting Live Animal Ultrasound Scanning Information

Live animal ultrasound scanning measurements, in association with abattoir carcase data, are used to calculate Carcase EBVs within the TransTasman Angus Cattle Evaluation (TACE).

What is live animal ultrasound scanning?

Live animal ultrasound scanning is a non-invasive technology that allows the seedstock or commercial beef producer to assess the carcase merit of an individual animal whilst still alive as opposed to the collection of carcase data in the chiller.

The carcase attributes most commonly measured by ultrasound scanning include:

Rump

Fat Depth

Rump Fat Depth is measured at the P8 rump site. The P8 rump site is located at the intersection of the line from the high bone (third sacral vertebrae) with a line from the inside of the pin bone. Rump Fat Depth will be reported to the nearest mm (e.g. 10 mm).

Rib Fat Depth

Rib Fat Depth is measured at the 12/13th rib site. The 12/13th rib site is located on the longissimus dorsi muscle (eye muscle) between the 12th & 13th rib. Rib Fat Depth will be reported to the nearest mm (e.g. 7 mm).

Eye Muscle Area

Eye Muscle Area is measured as the cross sectional area of the longissimus dorsi muscle between the 12th & 13th rib. EMA is reported to the nearest cm2 (e.g.110 cm2). Eye Muscle Area is also referred to as Rib Eye Area.

Intramuscular Fat (IMF)

The carcase benchmark for intra-muscular fat is the chemical extraction of all fat from a meat sample taken as a slice off the longissimus dorsi between the 12th & 13th ribs. Ultrasound scanning for IMF uses a longitudinal image of the longissimus dorsi muscle between the 12th & 13th ribs. IMF is reported as a percentage (eg 3.5%).

Use of accredited scanning technicians

TACE can only accept live animal ultrasound scanning measurements that have been collected by an accredited technician. A list of accredited technicians can be accessed from the TACE area of the Angus Australia website, or by contacting staff at Angus Australia.

Submission of scanning information is the breeder’s responsibility, not the accredited technician.

Which animals should be scanned?

While bulls are most commonly scanned, it is recommended that both bulls and heifers are scanned. Heifers provide valuable data for IMF as they mature earlier and better express genetic differences than males. While often cost prohibitive, scanning steers will also provide useful information for their sires and dams.

When should animals be scanned?

TACE can analyse live animal ultrasound scanning measurements from animals that are between 300 – 800 days of age at scanning. It is important to scan animals when they are within this age range, with the majority of animals being scanned as either yearlings or rising 2 year olds (i.e. around 600 days of age).

It is critical that animals are in appropriate condition when live animal ultrasound scanning measurements are collected and consequently, condition of stock should be the most important consideration when making a decision about when to scan animals.

Scanning animals when they are in appropriate condition ensures that there will be sufficient variation between animals to allow genetic differences to show up. If all animals are in very poor condition it would be expected that they would all have very similar rib & rump fat depths (i.e. 1-2 mm) and negligible marbling. In this scenario, scanning would be of little benefit as a means of identifying animals that are genetically different for fat depth and genetically superior for IMF. Effective results may still be achieved for EMA as sufficient variation is likely to exist between animals irrespective of condition.

As a rough guide, animals require a minimum average rump fat depth of 4–5 mm (or a minimum average rib fat measurement of 3 mm) to facilitate the collection of useful scanning measurements. Results for IMF will be further optimised if the majority of animals have between approximately 2 – 8% IMF when scanned. The effectiveness of the current scanning machines decreases when measuring IMF levels outside this range.

If animals have been in poor condition and have put on the required 4 - 5 mm of fat in a relatively short period, then there may still not be sufficient variation between animals to allow genetic differences to show up, particularly for IMF. Members who are in any doubt regarding when to scan their animals, should discuss their situation with an accredited scanner or contact staff at Angus Australia.

The availability of accredited technicians will also influence the time of scanning, but should not be a major determinant.

• While more than one set of live animal ultrasound scanning measurements can be collected for an individual animal, TACE is only analysing the first EMA, rib fat, rump fat and IMF measurement for each animal at this stage. Consequently, it is only necessary to collect one set of ultrasound scanning measurements on each animal for TACE. While all traits are typically measured on the same day, it is possible to submit EMA, rib fat, rump fat and IMF measurements where the individual traits have been measured on different days.

• It is important to try and scan as many animals within each management group as possible. Submission of live animal ultrasound scanning measurements for only a selection of calves (e.g. only submitting the scanning performance of sale bulls rather than the entire bull drop) may result in data biases and the subsequent calculation of carcase EBVs that do not reflect the true genetic merit of animals.

• A management group should be recorded for any animals or group of animals that have been treated differently or exposed to significant nongenetic influences prior to measurement that may affect their live animal ultrasound scanning measurements. For example, the scanning measurements for animals given a supplement should be recorded in a different management group to those without a supplement. Consideration should also be given to variations in pasture quality, stocking rates, water quality, etc.

• Live animal ultrasound scanning measurements should be recorded for all animals in a contemporary group on the same day. TACE will not directly compare scanning measurements collected on different days.

• Live animal ultrasound scanning measurements should be collected when animals are in as large a group as possible. Consequently, try to collect scanning measurements before any of the animals in a management group are treated differently. For example, before some bulls are joined.

Collecting Abattoir Carcase Information

Abattoir carcase information, along with live animal ultrasound scanning measurements, is used to calculate Carcase EBVs within the TransTasman Angus Cattle Evaluation (TACE).

Why collect abattoir carcase information?

Traits such as carcase yield and meat quality are some of the most economically important traits in the beef supply chain.

While the collection of carcase information from ultrasound scanning provides useful information on live animals, abattoir carcase information is of particular value for genetic evaluation as it represents a direct measure of the attributes of a beef carcase.

Obtaining direct abattoir carcase measurements can add considerable accuracy to the Carcase EBVs calculated within TACE, and consequently provides a valuable source of information when attempting to identify animals with superior carcase genetics for use in a beef breeding program.

How much effort is involved?

Members who are considering embarking on the collection of abattoir carcase information for TACE need to be aware that the collection of abattoir information can be challenging, expensive and time consuming.

The rewards however are significant and if useful abattoir information can be collected, the benefits can be considerable.

What abattoir carcase information will be accepted?

Abattoir carcase information must meet certain requirements in order to be accepted for inclusion in TACE. These requirements have been put in place to ensure any abattoir carcase information that is analysed within TACE meets appropriate data integrity standards.

Specifically, abattoir carcase information will be only be accepted for inclusion in TACE if:

• It has been collected as part of a structured progeny test program

• Appropriate measurement collection protocol have been followed to ensure the carcase measurements that are collected are of suitable quality for genetic evaluation

• Animals are between 300 and 1000 days of age at slaughter (i.e. 10 – 33 months).

Abattoir carcase information that does not meet these criteria, such as kill sheets for small groups of steers or

cull heifers, or information collected as part of a carcase competition, is not suitable for inclusion in TACE.

Carcase weight, rump fat, eye muscle area, MSA marble score and intramuscular fat measurements are currently utilised in the calculation of Carcase EBVs within TACE, however other measurements that have been collected can be submitted for storage on the Angus Australia database and possible future analysis.

Establishing a progeny test for the collection of abattoir carcase information

It is essential that any abattoir carcase information collected for inclusion in TACE is from a structured progeny test program in order to ensure that the amount of useful information generated is maximised.

Number of effective progeny per sire

Ensuring that there are an adequate number of effective progeny by each sire is an important consideration when designing a progeny test program.

The number of effective progeny per sire (EPN) takes into account not only the number of progeny by each sire, but how useful the information collected on those progeny are for genetic evaluation.

The number of effective progeny for an individual sire can be calculated by considering the number of progeny within a contemporary group that are by the sire compared with the number of progeny in the contemporary group sired by other bulls.

A contemporary group can be considered to be animals of the same sex which are born within an individual herd in a 60 day period and are managed together as one mob under the same conditions until slaughter.

Specifically, the number of effective progeny for a sire can be calculated as follows:

For example, if a sire has 5 progeny in a contemporary group of 10 animals, then the effective progeny number would be 5 x (5/10) = 2.5 progeny.

The following table provides a guide to the impact on the effective progeny number as the number of progeny by a sire, and the number of progeny by other sires changes within a contemporary group.

EPN = No. of Sire’s Progeny

No. of Progeny by Other Sires

No. of Animals in Contemporary Group x

Ideally sufficient females should be joined within the progeny test program to obtain a total effective progeny number of at least 10 - 15 per sire. This should give an EBV accuracy above 65-70% for a carcase trait with a heritability of 30%.

Genetic linkage (within Progeny Test)

In progeny tests where there are multiple contemporary groups (either within a single herd or across different herds), it is important to ensure that there are adequate genetic links between contemporary groups.

Genetic linkage enables the abattoir carcase measurements collected on animals in the different contemporary groups to be compared, while also enabling adjustment for differences in the genetic merit of the females to which the bulls are joined in each contemporary group.

If it is not possible for common sires to be represented in each different contemporary group, a minimum requirement would be to ensure that at least some of the bulls used have common sires, hence creating genetic linkage between contemporary groups through common grand-sires.

Genetic linkage (with the TACE Analysis)

If the bulls being progeny tested are largely of unknown genetics, it is important that reference sires are included in order to enable the abattoir carcase measurements to be linked to the carcase information that has been collected for other animals within the Angus breed.

The reference sires should ideally be “proven” bulls that have Carcase EBVs with at least 80% accuracy.

Allocation of dams

It is important to carefully consider the dams to which the bulls will be joined in any progeny test program for the collection of abattoir carcase information.

• Ideally the sires being progeny tested will be joined to dams of known carcase genetics (e.g. registered or previously registered females with Carcase EBVs).

• If dams of unknown carcase genetics are being joined (e.g. commercial females), it is important that dams are randomly allocated to each sire (i.e. no selective mating).

• Where females of several age classes are used, it is important to allocate females evenly across the age classes.

• Dams should ideally be straight bred Angus dams, but cows of another breed or crossbred cows can also be joined as part of a progeny test. It is however important that all cows joined are of the same breed (or similar cross).

• At a minimum, all dams should be individually identified (i.e. tagged), with the year of birth and breed composition of each dam recorded with Angus Australia to account for age of dam and breed effects.

Animal identification

It is important that all animals within the progeny test are clearly identified. This includes the dams to which the sires will be joined, plus all progeny.

Ideally, two forms of identification should be used to enable animals to be identified when tags are lost. For example, progeny may be tagged with a management tag at or shortly after birth, followed by a NLIS tag at marking.

Recording birth date information

It is important that appropriate details are recorded on all progeny at birth to enable the most effective analysis of the abattoir carcase information that is collected.

• The birth date of all calves needs to be recorded as accurately as possible. TACE will make adjustments to the abattoir carcase measurements to account for any differences in age between animals.

• The dam of each calf needs to be recorded. TACE will make adjustments to the abattoir carcase measurements to account for differences in the age and breed of the dam.

• If any calves have been bred by embryo transfer (ET), details regarding the recipient dam needs to be recorded. TACE will make adjustments to the abattoir carcase .

• The birth number of each calf needs to be recorded. That is, whether the calf is a single or twin calf. TACE will not directly compare the abattoir carcase measurements of single and twin calves together, and in general, twin calves should be removed from the progeny test.

Maintenance of contemporary groups (on farm)

Where practical, all animals within a contemporary group (i.e. animals of the same sex which are born within an individual herd in a 60 day period) need to be managed together as one mob under the same conditions from birth until slaughter.

Splitting contemporary groups into different mobs will reduce the effectiveness of the abattoir carcase information that is collected. Likewise, “culling” any animals from the progeny test will potentially bias the abattoir carcase information.

Splitting contemporary groups (on farm)

If it necessary to split contemporary groups, either onfarm or as animals enter a feedlot for grain finishing, it is essential that a) the contemporary group is only split based on differences in weight; b) all animals within the contemporary group are weighed at the time the contemporary group is split; and c) these weights are analysed within TACE.

Splitting the contemporary based on other criteria, or based on a weight that is not analysed in TACE, will potentially bias the abattoir carcase information.

Maintenance of contemporary groups (at slaughter)

All animals within a contemporary group should be slaughtered on the same day and at the same abattoir.

Animals within a contemporary group should not be “harvested” and slaughtered on different days as different portions of the contemporary group meet market specifications.

Harvesting animals as they meet market specifications will bias the Carcase EBVs that are calculated from the abattoir carcase information, with the information not accurately reflecting the variation in performance within the contemporary group, while also influencing sire representation in each sub-group.

Splitting contemporary groups (at slaughter)

If it is necessary to split contemporary groups at slaughter, it is essential that a) all animals are slaughtered within 14 days; b) each sire is equally represented in each sub-group; and c) there is no difference in the average carcase performance of each sub-group.

For example, if a contemporary group needs to be slaughtered across two different days, then progeny by each sire should be randomly selected for each slaughter group, and the contemporary group should be evenly split to try and ensure the average carcase performance of animals in each sub-group is similar.

Recording management group information

It is important that any animals within a contemporary group whose performance may have been affected by different non-genetic factors are clearly identified by specifying a different management group (or kill group) for the animals when submitting the abattoir carcase information to TACE. For example, animals that may have been split into a different mob for management purposes, or animals that have been affected by injury or sickness.

It is important to record a management group if animals have been affected by non-genetic factors at any time from birth up until slaughter. If animals are being finished in a feedlot, this includes details of any animals who may have been shy feeders, or who may have been removed from the group for health treatments.

Abattoir measurement collection protocols to ensure data integrity

When obtaining abattoir carcase information for inclusion in TACE, it is important to investigate how the carcases will be processed at the abattoir and how the carcase measurements will be collected to ensure that any information collected is useful for genetic evaluation.

In reality this can be difficult when carcases are being processed through commercially operated abattoirs, however abattoir measurements that have not been collected in accordance with appropriate measurement collection protocols can lead to considerable bias in the Carcase EBVs that are calculated for animals within TACE.

Use of MSA accredited graders

Where possible, animals should be processed at a Meat Standards Australia (MSA) licensed abattoir and have measurements collected by an MSA accredited grader. A list of MSA licensed abattoirs is available from the Meat & Livestock Australia (MLA) website.

It is important that the same MSA accredited grader collects carcase measurements on all animals within a contemporary group. Where carcase measurements are collected by different graders, a different management group (or kill group) should be specified for the carcases assessed by each grader.

Animal identification in the abattoir

Loss of individual animal and carcase identification is a common problem when collecting abattoir information for genetic evaluation.

All animals will have a management tag and NLIS tag at slaughter, with abattoirs routinely recording NLIS tag and body number. It is important that all identification information is carefully cross referenced to ensure that the abattoir measurements collected are appropriately assigned to the correct animals.

Processing of carcases

Several carcase processing procedures routinely practiced in commercial abattoirs can lead to a reduction in the usefulness of any abattoir carcase measurements for genetic evaluation.

• Hide puller damage - Fat can inadvertently be stripped from the carcase when the hide is being removed and can considerably bias the rump and rib fat measurements subsequently collected on the carcase. Fat measurements should not be submitted to TACE from carcases where considerable hide puller damage has occurred.

• Trimming – Fat will routinely be trimmed from carcases using a whizzer knife prior to carcase measurements being collected, especially from the rib fat measurement site. Rib fat measurements should not be submitted to TACE from carcases that have been trimmed.

• Carcase damage / Bruising - Carcases that may have considerable damage, bruising or abscesses can have portions removed during processing. Any measurements from these carcases should be carefully scrutinised and only submitted to TACE if the processing of the carcase has not biased the measurements collected.

• Quarter site – Carcases may be quartered at different sites. It is important that all carcases from animals in a contemporary group are quartered at the same site, and ideally at the 12/13th rib site. Where carcases have been quartered at a different site, a different management group (or kill group) should be specified.

• Spencer rolling – Some abattoirs undertake a practice known as “spencer rolling” to improve the shape of the cube roll. By design, spencer rolling distorts the eye muscle and subsequently biases any eye muscle area (EMA) and rib fat measurements that are collected. EMA and rib fat measurements should not be submitted to TACE from carcases that have been subject to spencer rolling.

• Electrical stimulation – All carcases from animals within a contemporary group should be subject to the same electrical stimulation process. This is particularly important when meat samples will be collected for analysis of meat tenderness.

• Chiller differences – Differences in chiller conditions (e.g. temperature), or differences in the length of time between slaughter and the collection of measurements in the chiller can have an influence on the carcase measurement values that are collected. A separate management group should be recorded to clearly identify any carcases from within a contemporary group that are stored in different chillers, or to identify any carcases for which there has been a significant difference in the length of time before measurement.

Collection of Meat Science Laboratory results

In addition to carcase measurements collected in the abattoir, meat samples can be collected from carcases for further analysis in the meat science laboratory for traits such as intramuscular fat (IMF), meat tenderness and meat colour.

Meat science laboratory measurements are expensive and are normally only collected in research trials, however members interested in obtaining meat science laboratory measurements should contact staff at Angus Australia to discuss what is involved.

Reviewing quality of measurements

Prior to submission to TACE, it is important that any abattoir carcase measurements are carefully scrutinised. Specifically, the measurements should be reviewed to ensure they fit within normal expected ranges, and that the variation between measurements is reviewed to ensure that measurements follow a normal expected distribution.

Collecting Docility Information

Docility scores taken on calves between 60 and 400 days of age are used to calculate Docility EBVs within the TransTasman Angus Cattle Evaluation (TACE).

Recording docility scores

Animals can be scored for docility using either a crush or yard test:

• Crush Test - Calves are put up a race and held in a crush or weigh scales for a minimum of 10 seconds (but not necessarily head bailed).

• Yard Test - Calves are individually put into a small square yard and the handler attempts to hold the animal in one corner for a minimum of 10 seconds.

While docility scores from both scoring systems are acceptable, the crush test is more commonly used as animals can be scored when moving through the crush for other purposes (e.g. weighing, animal health treatments).

Docility score descriptions

When using either the crush or yard test, the behaviour of animals should be observed and animals scored using the criteria displayed in the following table.

Half scores (i.e. 1.5, 2.5, 3.5, 4.5) can be used to identify animals who exhibit behaviour which is intermediate to the scores listed.

In a “normal” Angus beef herd where the majority of animals have acceptable temperament, it would be expected that the majority of animals would have a score of 1, 1.5 or 2, with a small percentage of animals receiving a score of 2.5 and above.

Docility Scores for TACE

1 Docile Mild disposition, gentle and easily handled, stands and moves slowly during handling, undisturbed, settled, somewhat dull, does not pull on headgate when in crush, exits crush calmly.

2 Restless Quiet but slightly restless, may be stubborn during handling, may try to back out of crush, pulls back on headgate, some flicking of tail, exits crush promptly.

3 Nervous Manageable but nervous and impatient, a moderate amount of struggling, movement and tail flicking, repeated pushing and pulling on headgate, exits crush briskly.

4 Flighty

When should animals be scored?

Docility scores must be recorded when animals are between 60 and 400 days of age for inclusion in TACE. The recommended time of scoring is at weaning or shortly afterwards. The advantage of scoring at weaning is that all calves should have had minimal handling and so will express variation in temperament. Variation in handling between animals prior to scoring should also be minimised.

Only one docility score can be analysed in TACE for each individual animal.

5 Aggressive

Jumpy and out of control, quivers and struggles violently, may bellow and froth at mouth, continuous tail flicking, defecates and urinates during handling, frantically runs fence line and may jump when penned individually, exhibits long flight distance and exits crush wildly.

May be similar to score 4 but with added aggressive behaviour, fearful, extreme agitation, continuous movement which may include jumping and bellowing while in crush, exits crush frantically and may exhibit attack behaviour when handled alone.

• There needs to be some variation in scores for them to be used in the TACE analysis. Scoring all animals in a group with a docility score of [1] does not identify any differences in docility between animals, and consequently does not provide any useful information for the calculation of Docility EBVs.

• Docility scores should be collected for all animals in a contemporary group. Only recording docility scores for a subset of animals is of no value and can lead to biased Docility EBVs.

• All animals in a contemporary group should be scored on the same day. TACE will not directly compare the docility scores of animals that have been scored on different days.

• Docility scores should be collected when animals are in as large a group as possible. Consequently, try to collect docility scores before any of the animals in a management group are treated differently.

• If any animals being scored on a particular day have had a different level of handling prior to scoring, they should be assigned a different “docility management group”.

• The method of scoring used (i.e. crush or yard) should be specified when submitting the docility scores.

• It is important that both a consistent scoring method is used and the same person scores all animals that are being assessed in the herd on a particular day.

• While more than one docility score can be recorded for an individual animal, TACE is only analysing the first docility score for each animal at this stage.

Collecting Structural Soundness Scores

Subjective structural soundness scores collected on animals are used to calculate Claw Set, Foot Angle and Leg Angle EBVs with the TransTasman Angus Cattle Evaluation (TACE).

Recording structural soundness scores

Structural soundness scores for TACE are collected using the Beef Class Structural Assessment System.

Scores are collected using a 1 - 9 scoring system, where:

• A score of 5 is considered ideal

• Scores of 4 and 6 show slight variation from ideal, but this includes most animals. Any animal scoring 4 and 6 would be acceptable in any breeding program

• Scores of 3 and 7 show greater variation, but would be acceptable in most commercial breeding programs, however seedstock producers should be wary

• Scores of 2 and 8 are low scoring animals and should be looked at carefully before purchasing

• Scores of 1 and 9 should be considered culls Front and rear feet should be scored separately.

When should animals be scored?

TACE can analyse structural soundness scores from animals older than 320 days of age at scoring (i.e. 10 months), with an animal able to be scored multiple times across its life.

Scores on both young animals, and mature females can be analysed. In general, scoring animals once as yearlings (or rising 2 year olds), and mature females once per year is recommended. Scores can be collected at any time throughout the year.

Use of accredited technicians

Both breeder collected scores and scores collected by accredited technicians are analysed in TACE.

It is suggested that independent accredited assessors are used for the collection of scores on sale animals, or in situations where the breeder is not confident with scoring their animals.

A “Paddock Guide to Structural Scoring for Genetic Evaluation” is available from Angus Australia to assist any breeders wishing to collect structural scores for their animals.

• It is important to try and score as many animals within each contemporary group as possible. Collection of structural soundness scores for only a selection of animals (e.g. only collecting scores for sale bulls rather than the entire bull drop) may result in data biases and the subsequent calculation of Structural Soundness EBVs that do not reflect the true genetic merit of animals.

• There needs to be some variation in scores for them to be used in the TACE analysis. Scoring all animals in a group with a score of [5] does not identify any differences in structural soundness between animals, and consequently does not provide any useful information for the calculation of Structural Soundness EBVs.

• If there is variation from foot to foot or leg to leg, the score that is collected should reflect the worst foot and leg respectively.

• A management group should be recorded for any animals or group of animals that have been treated differently or exposed to significant nongenetic influences prior to measurement that may affect their structural soundness scores. For example, differences in feed, or animals being run on different types of country (i.e. soft, rocky).

• Structural soundness scores should be recorded for all animals in a contemporary group on the same day. TACE will not directly compare scores collected on different days.

• It is important the same person scores all animals within a management group to account for variation between scorers.

• If foot trimming is practiced, structural soundness scores should be collected prior to trimming so that differences between animals are accurately described.

• Structural scores can only be analysed in TACE for animals that have a prior 200 or 400 day weight included in the analysis. The most recent 200 or 400 day weight contemporary group forms an important criteria in determining the contemporary group in which structural soundness scores are analysed.

• Structural score information can also be collected for a range of other traits such as rear leg hind view, sheath and navel scores, udder evenness and attachment, teat size and shape and capacity. These scores are not currently included in the TACE analysis however they may be used to develop Structural Soundness EBVs for these traits in the future.

STRUCTURAL SOUNDNESS SCORES

Front & Rear Feet Claw Set

Reference: Shape (primarily curl) and evenness of the claw set.

Front & Rear Feet Angle

Reference: Strength of pastern, depth of heel and length of foot.

Rear Leg Side View

Steep feet angle (SA)

Shallow feet angle (SA)

Sickle

Open Divergent (OD)

Image supplied by American Angus

Image supplied by American Angus

Scissor claws (SC)

Collecting NET FEED INTAKE INFORMATION

Net feed intake information is used to calculate the Net Feed Intake (Feedlot) EBVs within the TransTasman Angus Cattle Evaluation (TACE).

Recording Net Feed Intake Information

Collection of net feed intake information can be conducted either ‘on-farm’, or at a ‘central-test’ facility (e.g. Tullimba Research Feedlot), and involves:

• collection of daily feed intake measurements

• collection of regular weights to assess the weight, and rate of weight gain of animals

The use of commercial feeding systems that automatically record feed intake of individually electronically identified animals is recommended. Currently most feed intake data is collected using GrowSafe feeding systems, however there are other collection systems such as the Calan Broadbent Feeding System that can effectively capture feed intake data.

How Much Effort is Involved?

Those who are considering collecting net feed intake information for TACE need to be aware that the collection of feed intake measurements must be collected in a standardised way, and can be challenging, expensive, and time consuming.

However, if effective net feed intake information can be collected and analysed through TACE, the benefits can be considerable.

What Animals Should Be Tested?

• Animals must be between 210 and 700 days of age at the commencement of the net feed intake test period

• Bulls, steers or heifers can be tested, however only animals of the same sex should be tested in the same pen.

• Animals should be allocated into pens based on their most recent contemporary group within the TACE analysis (e.g. contemporary groups in which the 400 day weights were analysed). In general, this will include animals of the same sex, born in the same herd, born within a 60 day period, and managed under the same conditions prior to net feed intake testing.

• Animals that are in small or single animal contemporary groups prior to the test (e.g. twins, animals that have been sick) should not be tested. The net feed intake information of these animals is of little value.

• For effective sire comparisons, it is recommended to have a minimum of five progeny per sire, and at least two sires represented in each pen.

• The number of animals in each pen should be maximised as it will provide more comparative information per animal.

• If it is necessary to split contemporary groups for the net feed intake test (e.g. due to pen size) then it is important that each sire’s progeny are equally represented in each pen. For example, if a contemporary group of 120 steers needs to be split into 3 pens due to the pen sizes of 40 head, then 1/3 of the progeny by each sire should be randomly selected for each pen.

Preparing Animals for Feed Intake Testing

• All animals should have comprehensive health treatments (e.g. 5 in 1 vaccine, internal and external parasite drench, Bovilis MH + IBR vaccine) prior to entering the test so that they have reduced risk of ill-health, have the ability to achieve their potential growth and feed intake performance, and are assessed on an equal basis.

• The animal identification system adopted must be appropriate for the feeding system used, and must be adequate to allow individual animal feed intake to be recorded. Commercially available automatic feeding systems (e.g. GrowSafe) require the use of a compatible electronic animal identification system such as NLIS tags. The electronic identification numbers must be cross referenced with the Angus Australia ident, and the Angus Australia ident specified when submitting the net feed intake measurements to Angus Australia.

• A minimum adjustment period of 21 days is recommended prior to commencement of the test to allow animals to adjust to the ration and the testing environment/equipment. This can be a combination of a ration in open bunks and then a ration in the feed intake facility. Assessments should be made during the adjustment period to monitor individual feed intakes and acceptance of the diet. If shy feeders are detected during this phase, it is recommended that they be separated from the rest of the group during the pretest adjustment period. Shy feeders or poor performers may have to be excluded before the feed intake test commences.

Collecting Feed Intake Measurements

• Feed intake measurements should be recorded for each individual animal each day (as kilograms of feed consumed).

• Daily feed intake measurements should be collected for a minimum test period of 70 days, with a minimum of 60 valid feed intake days per animal.

• Animals must be fed a constant ration, fed ad libitum during the test period.

• The ration used must consist of a minimum of 10.0 MJ metabolisable energy (ME) per kg dry matter (DM), and a minimum of 14% crude protein (CP) per kg dry matter (DM). Minimum levels for ME and CP ensure that potential growth rates are not restricted. It is recommended that a ration as close to 12 MJ/ kg DM as possible is used when collecting feed intake measurements for NFI-F EBVs.

• During the test period, it is strongly recommended that individual animal performance be monitored by way of regular checks (e.g. review of daily intake measurements and visual assessment). Sick animals may have to be removed from the test.

• Equipment should be carefully monitored during the test period to ensure that faulty equipment (feeding units, scales or identification systems) can be detected in time to allow repairs before data is lost and the test is invalidated.

Collecting Weight Information

It is essential that animals are weighed regularly during the feed intake test period as net feed intake is calculated by adjusting daily feed intake for an animal’s live weight and rate of weight gain across the duration of the test. Each animal must be weighed at the start and end of the test period, and at 14 day intervals during the test period.

All animals in a pen should be weighed as the one group, with animals weighed as promptly as possible after removal from the pen. There should not be any delay in weighing due to other procedures being conducted (e.g. ultrasound scanning). If other procedures are to be conducted, all animals in a pen should be weighed, and then animals run through a second time for the completion of the other procedure.

Collating Net Feed Intake Information for TACE

When collating net feed intake information for submission to Angus Australia, the following information needs to be recorded for each animal:

Information Description

Test Station Code of Test Station

Test ID

Unique code for the feed intake test, consisting of year at beginning of test (yyyy) and a test number (xx) e.g. 201601.

Animal ID Angus Australia Ident

Management Group Management group (usually pen number)

Sex Bull, Steer, Heifer

Feeding Procedure Auto (A), Manual (M)

Weighing Method Auto (A), Manual (M)

Ration Energy Density MJ ME/kg DM of ration fed during test

Start test date

End test date

Number of records in weight calculations

Number of animal weights in daily mean

Start test weight (kg)

End test weight (kg)

Daily Feed Intake (kg)

Date at start of feed intake test, excluding pre-test conditioning

Date at end of feed intake test

Number of weights used when fitting regression line to calculate start and end test weights

Average number of weights on same day from which mean weight (start and end) or daily weights for regression have been calculated. Usually 1, unless automatic weighing has been used

Weight on start test date, as calculated from fitted regression line (i.e. not actual weight)

Weight on end test date, as calculated from fitted regression line (i.e. not actual weight)

Average daily feed intake over the duration of the test period

Test Type Post Weaning (P), Finishing (F)

Calculating Average Daily Feed Intake

Having collected daily feed intake measurements for each animal during the test period, the average daily intake across the duration of the test needs to be calculated.

It is essential that only valid daily feed intake measurements are included in the calculation of average daily intake. That is, invalid feed intake records should be removed.

A feed intake measurement may be identified as being invalid on a particular day (for either a single animal, a single pen or across all pens) in the trial if:

• an animal becomes sick. Feed intake measurements should not be submitted if the sickness extends for more than 5 consecutive days.

• an animal loses the electronic ear tag and/or cannot be identified.

• a pen is out of feed for an extended period (i.e. not ad libitum).

Calculating Start & End Test Weights

The start and end test weights that need to be submitted to Angus Australia for each animal ARE NOT the actual weights recorded at the start and end of the test period, but rather need to be calculated by fitting a linear regression line across all weights collected for an individual animal during the test period. Fitting a regression line enables the animal’s weight and rate of weight gain across the entire duration of the test to be measured more accurately.

When fitting the regression line, it is important that the relationship between the different weights that have been taken on each individual animal is carefully scrutinised,

• there is loss of power or faulty equipment in a pen or in the whole system.

• there is a considerable difference between the amount of feed that has been placed in the feeding equipment and the amount of feed accounted for in the feed intake measurements recorded for animals in that pen.

• a rain event alters feed intake measurements substantially (uncommon).

• animals are off feed (i.e. removed from the pen) for an extended period for weighing or other procedures (e.g. ultrasound scanning). Quick weighing events, where animals are weighed pen at a time, are usually fine.

If there are too many invalid records for an animal, a pen or across all pens, the test period may need to be extended to ensure a minimum of 60 valid daily feed intake measurements for each individual animal, or alternatively, the feed intake measurements should be excluded for any individual animal with less than 60 valid measurements.

and any weights that are clearly incorrect (i.e. vary considerably from the regression line) excluded from the linear regression calculation. A minimum of 5 weights should be used when fitting the regression line.

A simple way of analysing the relationship between the different weights is the R squared value. Start and end weights should not be submitted for animals if the R squared value is not 0.9 or above.

A spreadsheet that can be used to fit the linear regression line, calculate the start and end test weights, and calculate the R squared value is available from the TACE section of the Angus Australia website.

Example of fitting a regression line to calculate start and end weights and R squared value for an individual animal

Specifying the Test Station

Standard codes should be specified to identify the test station in which the net feed intake information has been collected.

Code Test Station

TUL Tullimba Research Feedlot

TRN Trangie Research Station

KER Kerwee Feedlot

ZZZ On-Farm*

*Code ZZZ is used when the feed intake test is undertaken on farm.

Specifying Management Groups

A management group should be specified to identify any animals within a contemporary group whose net feed intake information (i.e. average daily feed intake / weights) may have been affected by considerable non-genetic factors.

Specifically, a different management group should be specified for animals in different pens, and pen differences will generally have an effect on feed intake performance. This is particularly important for animals that start their feed intake test on the same day in the same location.

Specifying the Test Type

The test type (P = post weaning / F = finishing) is used to determine the physiological stage at which the test is conducted and needs to be specified when submitting net feed intake information.

Test Type Description

• Young growing animals post weaning

Post

Weaning

Finishing

• Generally heifers or bulls

• Average start weight of less than 500 kg

• Fed a lower energy ration of ~ 10 MJ

• Animals in the finishing phase (i.e. laying down fat)

• Generally steers

• Average start weight greater that 500 kg

• Fed a higher ration ~ 12-13 MJ

Submitting Performance to Angus Australia

All data for the TransTasman Angus Cattle Evaluation (TACE) should be submitted directly to Angus Australia.

The format in which data can be submitted differs subject to the type of information being provided, with data potentially accepted in the one of the following formats:

• Compatible herd recording computer program

Many of the commercially available herd recording computer programs (e.g. StockBook, HerdMASTER, Cattlelink, koolcollect) have the facility to submit data electronically to Angus Australia.

• Microsoft Excel templates

Standard Microsoft Excel templates are available that enable data to be submitted electronically to Angus Australia. Copies of the templates are available from the TACE area on the Angus Australia website, with different templates available for calf registrations,

Gestation length

Birth weight

200 day weight

Scrotal

Ultrasound

Structural

weights and scanning, structural score, abattoir carcase, and days to calving information.

• Submission facility on Angus Australia website

A facility is available on the Angus Australia website that enables the entry and electronic submission of data to Angus Australia.

• Paper forms

Standard pre-printed paper forms are available that enable data to be submitted to Angus Australia via mail or fax. Forms are available from Angus Australia, with different forms available for calf registrations, weights and mature cow weights.

Data should be submitted to TACE shortly after collection, with no limit on the number of times that data can be submitted throughout each year.

Submission deadlines for inclusion in TACE analyses are available from the TACE section on the Angus Australia website.

Submitted in association with calf registrations

Submitted in association with calf registrations

Recording sheet provided by accredited technician can be submitted provided it is presented in an acceptable format (including correct Angus Australia ident and management group information)

Recording sheet provided by accredited technician can be submitted provided it is presented in an acceptable format (including correct Angus Australia ident and management group information)

Contact Angus Australia to discuss alternative options if electronic submission of days to calving information is not possible

Contact Angus Australia to discuss alternative options if submission of

information using the

Recording Management Groups

Recording management group information is one of the most important aspects of collecting performance information for the TransTasman Angus Cattle Evaluation (TACE).

Why are management groups important?

TACE analyses cattle in contemporary groups to take out the influence of as many of the non-genetic effects as possible (e.g. management, nutrition, feed, year, season, injury, health status). The underlying principle is that only animals that have had an equal opportunity to perform are directly compared together within each contemporary group.

If the contemporary groups are not correctly formed, the EBVs calculated will be less accurate and possibly misleading.

Most of the problems that breeders encounter in “believing” their TACE EBVs can be traced back to incorrect contemporary grouping – either calves being fragmented into isolated groups of only one or two animals (and thereby virtually eliminating those calves from any comparison with their peers) or by not differentiating between calves who performance has been influenced by different non-genetic factors (e.g. differences in management or feeding).

Importantly, the management groups that are submitted with each set of performance information have a major influence on which animals are directly compared within each contemporary group in the TACE analysis.

Types of management groups

There are two different types of management groups;

1. Birth Management Group: specified to describe any non-genetic factors prior to calving that may result in differences to the performance measurements that are collected at birth (i.e. calving ease, birth weight, gestation length).

For example, where one group of cows have been supplementary fed during gestation, resulting in heavier calf birth weights than would otherwise be the case if they ware managed in a similar manner to other cows who haven’t been supplementary fed.

2. Post Birth Management Group: specified to describe any non-genetic factors post birth that may result in differences to the performance measurements that are collected.

For example, when some animals were run on an oats crop, resulting in heavier weights than would have been

the case if they were managed in a similar manner to other animals that were run on native pasture.

Specifying management group information is an important consideration when submitting any performance information to TACE. By assigning animals into management groups, seedstock breeders are acting as “eyes” for the TACE evaluation and ensuring that only the performance for animals that have had the same opportunity to perform is directly compared together.

Assigning management groups

Animals should be assigned into different management groups in any situation where their performance has been affected by different non-genetic influences to other animals. In practical terms, animals that have been run in the same contemporary group and have had equal opportunity to perform should be grouped together. Some examples of where animals should be recorded in separate management groups are:

• grain fed animals versus paddock reared animals

• some animals are fed for show or sale

• some animals being given growth promotants

• animals reared in different paddocks in which feed is of different nutritional value

• sickness gives some calves a permanent set back

• a bull has been fighting and clearly lost weight prior to recording

• yearling bulls used as sires compared to those not used as sires

• different stages of pregnancy for heifers (try to weigh before joining and certainly before two months)

• calves weighed on different scales

• calves weighed straight from the paddock as compared to those off feed for say three hours or more

• calves that are orphaned

Common Performance Recording Problems

The term “rubbish in – rubbish out” is often used when discussing the requirements of performance recording with the TransTasman Angus Cattle Evaluation (TACE). In other words, the reliability of the Estimated Breeding Values (EBVs) that are produced for the animals in a seedstock herd is a direct reflection of the reliability (or quality) of the information that is submitted to Angus Australia.

The reliability of performance information is influenced by many factors, with the accuracy of the measurements that have been collected and/or the submission of false information by dishonest breeders often being the first things that spring to mind.

In reality however, the majority of performance quality problems are caused by the submission of performance information that is simply of limited use for genetic evaluation.

This fact sheet outlines some of the most common issues that cause seedstock producers problems when performance recording with Angus Australia.

Importantly, the steps that seedstock producers can take to avoid these problems are also detailed.

Careful consideration of this information allows seedstock producers to take a large step towards ensuring that they are maximising the returns from their investment in performance recording, and in turn, the reliability of the TACE EBVs that they are obtaining for their animals.

Problem 1 – Inadequate Planning

A considerable number of performance recording problems stem back to inadequate planning (or inadequate priority) being given to the performance recording requirements of a seedstock herd.

In this scenario, little planning goes into the management of the herd so that the value of any collected performance data is maximised.

Herds will often not record the required performance, will record performance information in an ad hoc manner and in a lot of situations, any performance information that is recorded is largely an afterthought.

In layman’s terms, these herds may be classed as “reactive” or “casual” performance recorders.

Solutions

• Become a “proactive” performance recorder.

• Incorporate the collection of performance information into the standard management of your herd.

• Plan data collection ahead of time.

• Submit data to TACE shortly after data collection.

Problem 2 – Poor Recording of Traits of Importance

TACE currently has the potential to produce many different EBVs on each particular animal. While it is possible to generate “reliable” EBVs from pedigree information and performance that has been recorded for correlated traits, generally speaking EBVs will be of lower reliability if animals haven’t been directlyrecorded for the trait of interest.

Problems often occur when seedstock producers don’t adequately record the traits of importance within either their breeding objective or the breeding objective of their clients.

Solutions

• Record all traits that are important to either you or your clients.

• Do not rely on pedigree and minimal trait recording to generate EBVs that will be used in making selection decisions.

Problem 3 – Poor Genetic Linkage

Genetic linkage across contemporary groups both within a herd and between different herds is of fundamental importance in allowing the generation of TACE EBVs. Unfortunately, some common management practices can reduce genetic linkage significantly.

Such management practices include:

(i) Within herd

• Completely replacing all sires from one joining season to the next.

• Managing the calves from one sire differently to all other calves before recording any performance information.

• Not mixing cows after joining.

• All ET calves being by the same sire (and dam).

(ii) Across herd

• All sires used in the herd having no performance recorded progeny in any other herds (for a range of traits).

• AI calves in a herd being born at a separate time to those calves from natural matings.

Poor genetic linkage can cause significant performance recording problems.

Solutions

• Do not replace all sires from one year to the next so that across year comparisons can be made.

• Use sires that have progeny recorded for a range of traits in other herds.

• Mix cows after joining, particularly AI females.

• Manage calves by a range of sires together until after the key performance traits have been recorded.

• In ET programs, try to have a range of sires represented.

• Ensure calves from an AI program are born at a similar time to naturally conceived calves by your home bred sires.

Problem 4 – Poor Recording of Recipient Dam Information

There are now a considerable number of seedstock producers using embryo transfer within their breeding program. While TACE has the ability to analyse the performance of embryo transfer calves, inadequate recording of recipient dam information or use of recipient

dams of different breeds often results in performance recording problems.

Importantly, the amount of information available on the recipient dam determines how TACE uses the performance information of each ET calf.

Solutions

• Use recipient dams that are all the same breed when running an ET program.

• Ensure adequate recipient dam information is recorded with Angus Australia for each ET calf (i.e. tag no., specific breed and year of birth).

• Ideally, use “known” recipient dams. This includes recipient dams that have been used in previous ET programs or alternatively, stud cows that have TACE EBVs available (especially Milk EBVs).

Problem 5 – Unverified Outliers

As part of the ongoing verification of the performance information that is collected, TACE checks the variation in performance records between animals within each contemporary group.

While a certain degree of variation is expected within each group, when the difference between a performancerecord for an animal and the average of all animals in that contemporary group is greater than expected, the record for the animal is flagged as an outlier.

Each time an “outlier” is identified, an outlier report is forwarded to the relevant seedstock herd. This report gives the breeder the opportunity to correct or verify the performance for the “outlier” animal. If Angus Australia receives no response to the outlier report, the outlier records are excluded from all future TACE analyses. Ignoring outlier reports is a common cause of performance recording problems.

Solutions

• Pay attention to all information that you receive from the Angus Australia office.

• Verify/correct all outlier reports as soon as you receive them in the mail. If you are in any doubt, contact staff at Angus Australia for advice.

Problem 6 – Small Contemporary Groups

Although the TACE analysis is a very complex analytical model, the basic mechanism by which it works is to directly compare the performance of an animal with the performance of other “similar” animals within the same contemporary group.

Where only a small number of animals are represented in a contemporary group, there are only a few “similar” animals to which it’s performance can be directly compared and thus the performance submitted for it cannot be used effectively by the TACE analysis.

Small contemporary groups are a problem frequently experienced by smaller herds and without careful management, can result in considerable performance recording problems.

Solutions

• Restrict calving periods. A calving period of 6 to 8 weeks is optimal.

• Run as many calves as possible under the same management conditions.

• Weigh all animals in a management group on the same day.

• If a management group has to be split, weigh all calves before splitting the group e.g. all males before they are castrated.

• Create management groups based on “automatic” criteria e.g. sex, prior management groups, prior weigh dates.

• If you have a commercial herd of similar breed content to your stud animals, it may also be possible to record these animals with Angus Australia.

• In the situation where two herds run their animals together on the same property, set up an associate membership with TACE.

• Consider the use of genomic testing to complement any performance information that is collected.

Problem 7 – Single Sire Contemporary Groups

In the same way that it is important to have more than one calf represented in each contemporary group, it is also important to have the progeny from more than one sire represented within each contemporary group.

When all calves in a contemporary group are by the same sire, there are no other calves by other sires to which the performance of these calves can be directly compared.

In this manner, the performance submitted for those calves cannot be used effectively by the TACE analysis to calculate the EBVs of their sire.

Single sire contemporary groups are a problem that can be experienced by herds of all sizes and without careful management, can result in considerable performance recording problems.

Solutions

• Use more than one sire in each particular joining.

• Mix cows after joining.

• Consciously manage the herd so that more than one sire is represented in each contemporary group.

Problem 8 – Selective Performance Recording

Significant problems can arise when only selections of animals in a contemporary group are performance recorded. For example, only the performance for the best animals in the contemporary group is submitted to Angus Australia.

In this situation, the performance information for an animal will only be compared with the “selection” that has been recorded. If this “selection” is not an accurate reflection of the entire contemporary group, then TACE cannot make adequate comparisons and the EBVs produced may be biased or misleading.

The table provides an illustration of the problems caused by selective recording.

The problem caused by selective recording is demonstrated if we consider animal K7. In the first scenario, all 10 calves in the contemporary group have been recorded and K7 is 4 kg heavier than the average of the group (237 kg v’s 233 kg). This is an accurate reflection of how this animal ranks compared to his peers.

However, in the second scenario, the weights for the lightest 4 calves have not been recorded. K7 is now 15 kg lighter than the “average” of the group (237 kg v’s 252 kg). The selective recording of this group has resulted in the performance of K7 being compared against a misleading average. As TACE can only calculate EBVs based on the information that has been recorded, the subsequent EBVs that are calculated from this performance will also be misleading (i.e. biased).

Solutions

• Adopt a whole herd recording strategy.

• Record all calves with Angus Australia.

• Always record performance for all calves in a contemporary group and submit this performance to Angus Australia.

• Record performance on all available animals (i.e. heifers, bulls & steers, rather than just bulls).

Average 233 kg 252 kg

Problem 9 – Over Management Grouping

As identified in “Problem 6”, one common problem encountered is the separation of calves into isolated contemporary groups of only one or two animals (thereby virtually eliminating those calves from any comparison with their peers). While this is a problem in itself when calves are managed in small groups, issues can also arise when calves are part of a large contemporary group but their performance is analysed in small contemporary groups by TACE.

The common cause of this problem is the submission of many different management groups - even though calves are being run as part of the one large contemporary group.

Solutions

• Understand the criteria that automatically form contemporary groups in TACE (e.g. herd, calving year, sex).

• Only submit management groups for non genetic factors (e.g. sick animals, animals run under different conditions).

Problem 10 – Inadequate Management

Grouping

TACE analyses cattle in contemporary groups to take out the influence of as many of the non-genetic effects as possible (e.g. feeding, years, seasons).

The underlying principle is that only animals that have had an equal opportunity to perform are directly compared together within each contemporary group.

If the contemporary groups are not correctly formed, the EBVs calculated will be less accurate and possibly misleading. Most of the problems that breeders encounter in “believing” their TACE EBVs can be traced back to incorrect management grouping.

Poor management grouping will result in TACE not being able to differentiate between calves that have had different levels of management or feeding.

Solutions

• Understand the importance and role of management groups.

• Provide management groups for those animals that have been treated differently to their peers and have performed differently due to the nongenetic factors.

• If you are in any doubt, contact staff at Angus Australia for advice.

Problem 11 – Pedigree Errors

While not directly associated with performance information, one of the most common causes of problems with TACE EBVs is inaccurate pedigree information.

Even with a concerted effort to record accurate pedigrees, many situations can compromise the accuracy of pedigree information, including:

• In a naturally joined single sire joining mob there is always a possibility of another bull (known or unknown) mixing with the mob at some stage.

• Artificial breeding technologies can add considerable source of errors, particularly if the backup bull is put in soon after the AI program and there is not be a clear break in calving between the AI calves and calves sired by the backup bull.

• “Mothering up” cows and calves may be compromised by mismothering, particularly in first calf heifers.

• Human error when recording the mating details either from natural or artificial breeding programs.

Solutions

• Pay particular attention to recording pedigree information as accurately as possible.

• In situations where pedigree is unclear, consider the use of DNA parentage verification as a way of accurately determining animal parentage.

Problem 12 – Scanning Animals in Inadequate Condition

Collecting carcase measurements via live animal scanning when animals are not in adequate condition is a common problem experienced by seedstock members, especially when scanning yearling bulls.

When animals are scanned when they are not in adequate condition (i.e. they are too lean), the usefulness of the fat depth and IMF measurements is considerably reduced. In particular, very little variation is observed between animals for these traits, plus the ability of the scanning machines to accurately measure IMF decreases significantly when low levels of IMF are present.

In these scenarios, scanning is of little benefit as a means of identifying animals that are genetically different for fat depth and IMF%.

Solutions

• Ensure animals are in adequate condition at the time of scanning.

• As a rough guide, animals would be considered to be in adequate condition if they have a minimum average rump fat depth of 4 – 5mm (or average rib fat depth of 3mm) and the majority of animals have more than 2% IMF when scanned.

• Scan heifers as well as bulls.

Performance Recording in Small Herds

One of the most common questions asked by seedstock breeders is “what size herd do you need to obtain effective results from TACE?”

There is no minimum herd size requirement for herds wishing to participate in the TransTasman Angus Cattle Evaluation (TACE), however the nature of the TACE analysis means that there are a number of additional considerations that small herds need to make to ensure they obtain effective results from TACE.

In particular, small herds need to pay careful attention to two main concepts, being contemporary group formation and the creation of genetic linkage.

Contemporary Group Formation

Although the TACE analysis is underpinned by a very sophisticated analytical model, the basic mechanism by which it works is to directly compare the performance of an animal with the performance of other “similar” animals within the same contemporary group.

Put simply a contemporary group can be described as animals from the same herd, of a similar age and run under the same conditions i.e. animals that have had the same opportunity to perform.

For most performance traits, calves will be analysed in the same contemporary group if they:

• Were bred in the same herd

• Are of the same sex

• Are of the same birth number (i.e. twins are not compared to single calves)

• Are of the same birth status (i.e. ET calves are not compared to AI/natural calves)

• Were born in the same calving year

• Were born within 45 days (for birth and 200 day weight traits) or 60 days (for 400 & 600 day weight, scrotal and scanning traits) of each other

• Have performance recorded on the same day (& any previous measurements have been recorded on the same day)

• Have been run under the same conditions (breeder allocated management group)

Small herds must try and ensure there are at least two animals that meet the above criteria if their performance records are to be analysed effectively by TACE. When there is only one animal represented in a contemporary group, there are no other “similar” animals to which its performance can be directly compared and thus the performance submitted for the animal will not be used in the TACE analysis, rendering it ineffective.

As illustrated in Figure 1, the effectiveness of an individual animal’s performance record increases as more animals are represented within each contemporary group. The general aim for all small herds should be to maximise contemporary group size as much as possible.

Understanding Genetic Linkage

Genetic linkage gives the TACE analysis the ability to compare the performance of animals from different contemporary groups. This is particularly important for animals running under different conditions in different herds, but also relates to the comparison of animals running in different contemporary groups within a herd. For example, animals born in the same herd but born in different years.

For TACE to compare animals from different contemporary groups, be it in the same herd or in different herds, each contemporary group must have some performance recorded progeny from common animals (typically common sires) so that the performance recorded animals in each group are genetically linked.

As a simple example of genetic linkage, consider the scenario outlined in Figures 2 and 3 where 3 different mobs of calves are compared.

There are environmental differences between the groups – Contemporary Group 1 (CG1) has relatively poor nutrition, Contemporary Group 3 (CG3) is average and Contemporary Group 2 (CG2) is relatively good. All of the progeny in each group are by different sires (Kevin, Tony and Harold), with a common link sire (Malcolm) existing in each contemporary group.

While it is not possible to directly compare the performance of the calves in the different groups due to the environmental differences, the link sire makes it possible to compare the progeny of the different sires represented in each group by acting as a benchmark in each group.

When compared to the link sire Malcolm, Harold in contemporary group 3 can be considered to have the highest genetic value for 400 day weight performance, followed by Kevin in group 1, followed by Tony in group 2. Graphically, these differences are shown in Figure 3. For the purpose of this exercise, all sires are assumed to be joined to cows of equal genetic merit, although in practice, TACE accounts for any genetic differences that exist between the dams.

Management Strategies for Small Herds

Taking into consideration the concepts of contemporary group formation and genetic linkage, it becomes obvious that small herds, if not managed with these concepts in mind, may struggle to maximise the effectiveness of their performance recording.

Because of their low animal numbers, small herds tend to have high numbers of single animal contemporary groups, and may struggle to create genetic linkage, thereby reducing the effectiveness of their performance recording. There are however a variety of management strategies small herds can implement to increase the effectiveness of their performance recording, as outlined on the following page.

Creating Effective Contemporary Groups

Restricted calving periods – as calves are generally only included in the same contemporary group if they are born within 45 or 60 days of one another, it is recommended that small herds aim to have a restricted calving period. A calving period of 6 to 8 weeks is ideal.

Run all calves under the same management conditions – where possible, all calves should be run under the same management conditions. Where calves need to be split into different groups e.g. male calves into steers and bulls, weigh the whole group before it is split. Where possible, use the same criteria that will be used in TACE to split mobs. For example divide animals by sex of calf, by age of calf, by ET calves vs non-ET calves or by prior management groups.

Record performance for all animals on the same day – as TACE only directly compares the performance of animals that has been recorded on the same day, it is important to record the performance for all animals within a contemporary group on the same day e.g. weighing all heifers on the same day.

Inclusion of commercial/unregistered animals - many breeders have a small stud herd run in conjunction with commercial animals. If you have a commercial herd of similar breed content to your stud animals, it may also be possible to record these animals with Angus Australia. This will allow a greater number of animals to be included in the same contemporary group.

Associated Herds – In the situation where two herds run their animals together on the same property, Angus Australia can associate the two memberships to allow the performance of calves in both herds to be directly compared together.

Use more than one sire – The TACE analysis will be more effective if at least 2 sires are represented in each contemporary group as the performance of the progeny is going to contribute to the calculation of the EBVs of their sire. Where AI programs are used, they should be timed so that AI sired calves are born at the same time as calves sired by natural joining’s.

Supply recipient dam details – Herds that use embryo transfer need to identify the breed and age of the recipient dams of ET calves. If the breed of recipient dams is not supplied ET calves are split into single animal contemporary groups and therefore their performance is not effective. To maximise the analysis of ET calves by TACE, it is preferable if the recipient dams used are all of the same breed.

Creating Genetic Linkage

Use a range of sires – common sires link contemporary groups within a herd, across herds and across years.

In order to create genetic linkage across herds, it is recommended that where possible, sires bred or used by other herds who are performance recording with TACE, be used alongside home bred sires.

Use sires across years – do not replace all sires in the herd from one year to the next so that across year comparisons can be made.

Mix cows after joining – mixing cows that have been single sire joined, particularly AI females, after joining will create contemporary groups with more than one sire represented.

Increase Accuracy with Genomics

• In addition to the analysis of pedigree and performance information, TACE also incorporates DNA information from several different genomic products.

• By contrast to performance information, the effectiveness of genomic information within TACE does not increase as contemporary group size increases, and so testing animals with genomic products offers small herds with a valuable opportunity to increase the accuracy of the EBVs that are calculated for their animals, particularly in situations where it is not possible to collect effective performance information.

Performance Recording in a Drought

One of the challenges facing beef producers across Australia is the ever increasing occurrence of drought. Drought presents many obstacles to the management of a beef enterprise with countless operational, financial and emotional hurdles testing the resolve of beef producers.

While often not on the top of the priority list, one of the considerations that managers of a stud cattle operation need to make is the impact that the drought (and consequent management practices) has on both the genetics and performance recording requirements of their herd.

Why is it important to consider genetics?

Genetic improvement is a medium to long term strategy for improving herd profitability. Importantly, the effects of genetic improvement are both cumulative and permanent. The breeding decisions made in a herd today will have a direct impact on the genetics and subsequent profitability of the herd for the next ten years.

Consequently, stud breeders are encouraged to persist with their long term genetic improvement strategy during short term challenges such as drought. One component of this is the maintenance of an effective performance recording program.

Won’t the poor performance of animals in a drought lower their EBVs?

No. The performance of an animal will only be directly compared by the TransTasman Angus Cattle Evaluation (TACE) to the performance of other “similarly treated” animals. That is, calves that have been bred in the same herd, are of the same sex, are of similar age and have

been run together. It is how the animal performs relative to other “similarly treated” animals that is important, not the actual measurement of the animal.

What impact can a drought have on performance recording?

While the poor performance of animals is not a problem to genetic evaluation, there are countless factors that can potentially compromise the effectiveness of a herd’s performance recording during a drought. Generally speaking, these factors revolve around the forced implementation of management practices that cause considerable disruption to routine stud operations and/ or the poor condition of stock.

For example,

• Animals being placed on agistment, often on a number of properties, especially where the management of animals is largely uncontrolled unknown

• Early weaning of calves or a number of different early weanings Increased and varied incidence of disease sickness

• Dispersal of a large number of stud animals

What management practices can be taken to reduce the disruption of drought?

Importantly, there are a number of strategies that can be taken which will minimise the disruption that drought has on the effectiveness of a herd’s performance recording:

• Breeders should carefully consider the traits that are important to their breeding program (or the breeding program of their clients) and potentially rationalise the traits that they record. With time often a constraint, limiting your performance recording to a core of important traits can be an adequate interim measure. Alternatively, maintaining the traits that you record but limiting your performance recording to just your bull calves may be a suitable short term option. If utilising this option, it is important to resume whole herd and full trait recording as soon as possible.

• Where possible, the number of animals within each contemporary group should be maximised and/or maintained. TACE will use the performance information of an animal more effectively if there are a large number of other “similarly treated” animals to compare it with.

• If a contemporary group has to be split for management reasons, create the new groups based on “automatic” criteria (eg. sex, age, prior management groups, prior weigh dates). In addition, try to weigh all calves in the contemporary group before the group is split.

• Care should be given to submitting accurate management group information. A different management group code should be entered for any calf or group of calves that have either been treated differently or exposed to different non-genetic influences. For example, calves given different levels of supplement or calves placed on agistment. Consideration should also be given to variations in pasture quality, stocking rates, water quality, etc. In addition, a birth management group should be specified with the birth performance (eg. birth weights) of any calves whose dams have been treated differently prior to calving.

What other specific considerations should be made?

• In addition to the above management strategies, there are several specific considerations that need to be made when recording particular trait information.

• Only record scanning information on animals that are in adequate condition, especially when scanning for fat depth & IMF. To obtain effective results, animals should have a minimum average rump fat depth of 4 – 5 mm. This ensures that there will be sufficient variation between animals to allow genetic differences to show up.

• If early weaning, it is important to remember that TACE can only analyse the 200 day weights of calves that are older then 80 days of age when the weight is recorded. Consequently, if some calves will be younger than 80 days of age when you plan to wean, please contact staff at Angus Australia to discuss the performance recording options for these calves.

• TACE can analyse two 200 day weights on each animal. Therefore, if early weaning, it may be beneficial to weigh the calves at weaning and then take a later weight.

• In situations where the recording of the 200 day weights for your calves is delayed, it is important to remember that the recording of the associated mature cow weights should also be delayed so that they are taken within two weeks of the 200 day weights for the calves.

• The fertility performance of cows running under drought conditions can provide very valuable information to the TACE analysis. In drought situations, there will generally be more pressure placed on female fertility than normal and this can have benefits for genetic evaluation. However, the usefulness of the fertility information can decrease if there are significant non-genetic influences that can’t be accounted for (eg. disease). If you have any concerns over the quality of your fertility information in a drought, please contact staff at Angus Australia to discuss your concerns prior to submitting this information.

Should performance be recorded for calves that have lost weight?

Yes. Calves should be recorded even if they have lost weight. Remember that animals are only directly compared to other calves that have all been treated alike. It is how the animal performs relative to the other “similarly treated” animals that is important, not the actual performance of the animal.

Should performance be recorded for sick/ extremely poor animals?

In extreme situations, if the drought has resulted in a high and varied incidence of disease/sickness, careful consideration needs to be given as to whether to record the performance for that particular group of animals. If there have been significant differences in non-genetic influences that can’t be accounted for, recording performance may bias the EBVs of these calves. It is important to note that this relates not only to their performance during the drought, but all performance information for these calves. While the drought may have broken by the time their later performance is recorded, there may still be differences between the performance of the calves that can be attributed to the non-genetic influences that couldn’t be accounted for previously.

Does genomics offer an alternative to collecting performance information?

As a general rule, performance information should be collected and an effective performance recording program maintained wherever possible. However in situations where the collection of effective performance information is either challenging or not possible, genomically testing animals provides a useful alternative for obtaining information about the genetics of the animals.

Who

do I contact for advice?

The best approach to maintaining an effective performance recording program during a drought will vary from operation to operation and from drought to drought. If you are in any doubt as to the best strategy for your particular situation, please do not hesitate to contact staff at Angus Australia to discuss your options.

Collecting Genomic Information

Genomic information, obtained from a DNA sample of an animal, is combined with the pedigree and performance information that has been collected to calculate TACE Estimated Breeding Values (EBVs) for the animal of higher accuracy.

Which genomic product?

The TransTasman Angus Cattle Evaluation (TACE) incorporates genomic information from several different genomic products.

When making a decision as to what genomic product will be used, it is important to consider:

• The price of the genomic product, including the price of any add-on tests

• Testing turnaround times for the genomic product

Information regarding the different genomic products for which animals can be tested is available in the TACE section of the Angus Australia website.

It is important that DNA samples are submitted through Angus Australia. Results from genomic tests not conducted through Angus Australia will not be included in the TACE analysis.

Steps for collecting genomic information

The process for testing an Angus animal with any of the genomic products is the same:

Step 1

Ensure the animal is registered with Angus Australia. Registration forms are available from the Angus Australia website, or upon request from staff at Angus Australia.

Obtain equipment required for the collection of DNA samples. Items such as Hair collector kits and TSU racks are available for purchase from Angus Australia.

Step 2

Step 3

Obtain a DNA sample from the animal. Hair, tissue sampling units (TSU) or semen samples can be submitted to Angus Australia. If a hair sample is being provided and additional DNA testing is also required (such as testing for genetic condition status), it is advisable to collect two hair samples to ensure that adequate DNA is available.

Complete the DNA Test Request form that is available from the Angus Australia website, or upon request from staff at Angus Australia.

Step

4

Step 5

Return the completed DNA Test Request form and DNA sample to the address listed on the DNA Test Request form.

Cost of genomic testing

The cost of testing differs depending on the genomic test that is being conducted. Costs for the different genomic tests are available from the Angus Australia website.

Availability of results

Upon receipt of the DNA sample, the sample will be processed and forwarded to the relevant laboratory for testing.

Once the testing is completed, the genomic results are returned to Angus Australia and automatically stored on the Angus Australia database for inclusion in the next TACE analysis.

Results are usually available within 6-8 weeks.

When should DNA samples be collected?

DNA samples for genomic testing should be undertaken at a time that best fits in with other normal, routine management practices.

A good strategy is to collect samples on all calves at a young age (e.g. weaning) and store the samples for genomic testing at a later date. To best preserve the DNA sample, store them in a dry, dark environment.

TSUs can be purchased from Allflex suppliers and racks for postage can be obtained from Angus Australia. Nonlab specific hair collectors are also available for purchase from Angus Australia.

If collecting hair samples, collection should not be done on very young calves. It is recommended that animals are at least 60 days of age (2 months) before hair samples are collected as the hair follicles are small and still developing. Hair samples must have clearly visible follicles before they are suitable for testing however, tissue samples collected using a Tissue Sampling Unit (TSU) can be collected from as early as birth.

Ideally, having genomic information incorperated into the generation of EBVs, the verification of parentage and establishing genetic condition status is incredibly valuable at a young age. By utilising genomic information earlier, when an animal has very little other information collected on it, EBV accuracy can be bolstered and selection decisions can be made with confidence, earlier.

What animals should be tested?

In contrast to performance information, there is no requirement to collect DNA samples for all animals in a contemporary group.

Testing can consequently be conducted on as many or few animals as desired. Common testing strategies include:

• testing an individual animal

• strategically testing a group of animals of specific interest, for example candidate bulls for use in a breeding program

• testing an entire calf drop

When making a decision as to what animals will be tested, it is important to consider:

• Genomic information provides more value for animals whose EBVs are of low accuracy. Genomic testing is therefore more suited to calves, than sires or dams, or calves for which it is difficult to collect effective performance information (e.g. calves that may have been removed from their contemporary group, calves in smaller herds).

• Genomic information is of limited value if the animals being tested are not related to the animals within the genomic reference population. For this reason, it is recommended that members contact staff at Angus Australia for advice prior to testing animals recorded on the RAR or MBR registers.

• When collecting TSU samples ensure that the cap of the tissue is sealed tightly, with no hair obscuring the seal, that liquid is present within the TSU, with the float ball present and that the sample can be seen in the liquid.

• When collecting hair samples, check the identification of the animal and record the full Angus Australia ident on the front of the collection card.

• When collecting hair samples, pull a minimum of 40 hair follicles from the thick brush of the animal’s tail making sure the roots are still attached.

• Ensure the DNA sample collected is dry and free from any foreign matter (dirt, faeces and plant material). Dirty samples often fail testing and will require recollection.

• When collecting hair samples, place the hair sample in the collection card, align hair follicles and place the animal ident sticker over the hair shafts. Trim excess hair that falls below the card.

• It is essential that semen straws are protected prior to sending to Angus Australia. Semen straws are damaged easily and to avoid this take two pieces of cardboard and make a groove for the straw to sit in. Label and tape the cardboard together.

• Alternatively remove the ink from a pen and place the straw within the barrel of the pen, before returning the cap. Attach a label to the pen.

• When posting semen straws write “do not bend” on postage bag.

• Place samples and completed paperwork in a sturdy postage bag.

Measurement is the first step that leads to control and eventually to improvement. If you can’t measure something, you can’t understand it. If you can’t understand it, you can’t control it. If you can’t control it, you can’t improve it.

H. James Harrington

Further Information

To further discuss the collection and submission of any of the information discussed in this publication, please contact staff at Angus Australia.

Angus Australia

Locked Bag 11

Armidale NSW 2350

phone: (02) 6773 4600

email: office@angusaustralia.com.au

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