Beef HerdPlus
Journal 2014/15
The €uro-Star system a really quick explanation
‘I’m not interested in a bull’s figures. I’d rather see the bull myself in the flesh and make up my own mind as to how good or bad he is.’ ‘Sure how can they say he’s a 1 star bull, look at him, best looking bull I ever bred. Come around the back of him here and look at how wide he is – some bull’. It’s fair to say that some people see the breeding values that ICBF assigns to pedigree animals as being alien & unrelated to the actual cut & thrust of pedigree breeding. €uro-Stars are often seen as being conjured up by a computer that sits in an office and is operated by somebody that has never pulled on a pair of wellies or knows what a farmer looks like. It’s understandable that this image could flash through someone’s mind, particularly if they are disappointed with the €uro-Star ratings that have been awarded to one of their own animals. Fortunately, however this is not how ICBF actually produces genetic evaluations.
Stripping away all the technical jargon & scientific terminology attached to ‘Genetic Evaluations’, such as ‘correlations’ and ‘matrixes’, which can often be offputting – the easiest way to understand the process that ICBF follows when producing €uro-Stars is to think of the general process that a cattle judge will go through at a show before picking a winner. Take a class of bulls at a show for example: 1. All of the bulls in that class will be of a similar age. 2. The judge will normally inspect each bull individually in order to get an impression as to how well developed he is for particular traits of interest. Judges can often be seen running their hands over a bull’s hindquarter & loin as well as watching intently as the animal is walking – the whole time adding to their overall impression of the animal. 3. Finally the judge will line up the bulls, ranking them from 1st to last, based on the impression of the animals that was formed when they were being judged. So although no data is being recorded in writing or inputted into a computer in the above judging process, data about the animal is being stored in the judge’s mind and is subsequently used to decide on how the animals are ranked.
Archie McGregor (judge) in deep study, assessing the bull lineup at the All Ireland Bull & Heifer Derby 2007.
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Beef HerdPlus Now take the same class of bulls in terms of how their €uro-Star figures are calculated. 1. They are firstly assigned to groups depending on their age & sex, so that similar to the showring, they are treated fairly & not compared to animals that are a lot older or younger than them. 2. They are ‘judged’ on data that has been recorded on them and their herdmates. Previously recorded data on all known relatives of the animals in question is also included at this stage. The traits that are looked at here are ones that are ‘economically important’ e.g. Liveweight has a higher financial impact on a farmer than coat colour. 3. They are then ranked from 1st to last depending on how they compare for whatever the trait being evaluated is through the publication of ‘Breeding Values’. Finally then, the €uro-Stars themselves are just a way of making the breeding values visually easier to understand (no different to rosettes in the showring). The bottom line is that both a ‘show ring’ and a ‘genetic evaluation’ both work on the basis of recording information on an individual animal & then ranking that animal alongside its contemporaries or herdmates, based on how superior or inferior it is deemed to be. The ICBF database then stores all of these rankings and breeding values so as over time an increasingly accurate picture as to how a bloodline is performing is built up. For example, if the majority of the progeny for ‘Bull A’ are constantly being born with no calving difficulty when compared to other calves being born in the same herd, then ‘Bull A’ will receive a calving difficulty % figure that reflects the fact that he is an easy calving bull.
The ICBF Database acts as the ‘judge’ in a genetic evaluation run.
Example 1 – Calving Difficulty% The NCBC Angus AI Bull ‘KYA’ received a ‘Calving Difficulty %’ breeding value of ‘0.90%’ with a reliability of 99% when ICBF ran its August 2014 genetic evaluations. The average for the Angus breed is ‘2.25%’ so he is rated as being an extremely easy calving Angus AI Bull. The table overleaf gives a summary of what data was used in the genetic evaluations to arrive at this conclusion. Judging in progress at the All Ireland Angus bull calf championship at the Iverk agricultural show in Piltown, Co.Kilkenny (photo:Irish Farmers Journal).
The genetic evaluation process is actually quite similar to the process that is followed in a Showring when cattle are being judged. Journal 2014/15
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Beef HerdPlus
Calves sired by ‘ KYA’ were born more easily than other calves born in the same herds at the same time. Bull ID
KYA
Date of
His calves were also easily born across various ages of cows.
Number
Herd
Scored
Herd
Male
Evaluation of Births
Mate Births
3 or 4 (%)
Mate Scored 3 or 4 (%)
Births
24226
2
3
3004 (52%)
Aug-14
5740
1st Parity
2nd Parity
3rd Parity
Records
Scored 3 or 4 (%)
Records
Scored 3 or 4 (%)
Records
Scored 3 or 4 (%)
3560
3%
850
1%
1423
2%
This easy calving data then gets converted into an easy calving breeding value.
Breed Average figures are always printed so as it is easier to gauge how easy or hard calving a bull is. Reliability % Referencing the showring again – if there was only one bull in a class at a show and he was crowned as being the champion – it would’nt carry much weight. Similarly for genetic evaluations, if an animal is weighed on its own or with
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only a few other animals then the reliability % figure on the breeding value for ‘liveweight’ for that animal will not increase that much, reflecting the type of data that came in. However if lots of animals are involved then the reliability % figure will rise much higher (as in the previous example of ‘KYA’).
Journal 2014/15
Beef HerdPlus Example 2 – Carcass Weight The Dovea Genetics Charolais AI Bull ‘CXY’ received a ‘Carcass Weight’ breeding value of ’44 Kgs’ with a reliability of 99% when ICBF ran its August 2014 genetic evaluations. This made him a 5 Star bull for this trait so he is rated as
being an extremely good bull for siring stock with heavy carcass weights.
Cattle sired by ‘ CXY’ were ready for slaughter earlier than their herdmates.
On average, his progeny also returned heavier carcasses than those of their herdmates
Bull ID
Date of Evaluation
Progeny Carcasse
Herd Mate Carcasses
CXY
Aug-14
832
18,923
Similar to the Angus example, the following tables give a summary of how his 5 Star rating was achieved.
Average Age at slaughter (Days) Progeny Herdmates
Progeny
Herdmates
Progeny
Herdmates
683 days
386 kgs
374 kgs
U-
U-
719 days
Carcass Weight (Kg)
Conformation
Again, this data is extracted from the ICBF database and used in CXY’ s €uro-Star evaluation
Journal 2014/15
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Beef HerdPlus So ‘CXY’ & ‘KYA’ do go through a ‘judgement process’, however instead of this consisting of them parading in front of a judge it is based on the performance of their progeny compared to that of their herdmates for traits that could make or lose farmers money in farms, marts and factories across Ireland.
ICBF groups all of these economically important traits together under 2 headings called the ‘Terminal Index’ and the ‘Replacement Index’. Each trait is given a different percentage weighting depending on it’s economic importance.
Terminal Index
Replacement Index
This is an indication as to how profitable progeny of the bull will be, when they are sold or slaughtered.
This is an indication as to how profitable daughters of the bull will be when they calve down.
E.g. A Bull with a Terminal Index of €148 is expected to sire cattle for the meat industry that are €148 more profitable than the average animal.
E.g. A Bull with a Maternal Index of €264 is expected to sire daughters that are €264 more profitable than the average Irish suckler cow.
Traits
% Emphasis
Calving
29%
Beef
68%
Docility
3%
It is worth remembering that although broad similarities have been described in this article between the showring and how €uro-Stars are calculated – this is largely for ease of explanation purposes. A genetic evaluation run involves a series of complex computer programs where numerous mathematical formulae, algebraic equations & statistical procedures are used to disentangle the environmental influences on an animal’s performance from the genetic ones. It is also important to remember that there are traits that are biological and for which a person’s opinion will not work. Traits like ‘Fertility’, ‘Feed Conversion Efficiency’,’ Somatic Cell counts’ etc fall into this category.
Traits Calving Beef Fertility Milk Docility
% Emphasis 24% 43% 19% 11% 3%
Catalogue Page All of the most important traits are displayed on an animal’s catalogue page or bull search output. The graphic overleaf describes the layout of a catalogue page.
The majority of sales catalogues published across the breeds are now available online and follow the same template, with ancestry and €uro-Stars being shown in the same format. This makes it quick & easy for purchasers to compare bulls from different breeds and sales against each other. Photo:Irish Charolais Society Website - Sales Catalogue section.
€uro-Stars are not plucked from the night’s sky. They are scientific ratings that are based on data recorded in Irish farms, marts & factories.
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Journal 2014/15
Journal 2014/15
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0.5 Star
1. Look at the Reliability % figures. • Reliability % is the most important figure to look at on a bull’s catalogue page. • ALWAYS look at the reliability % figure BEFORE looking at a Bull’s €uro-Stars or breeding values. – They tell you how much importance you should attach to a Bull’s figures when deciding whether to purchase him or not. • Any young bull that has not yet sired a calf will not have a reliability % figure greater than 50%.
Understand a Bull’s Catalogue page in 3 steps…
As more information is included in a Bull’s genetic evaluation the reliability % of those genetic evaluation results increases.
2. Look at the Overall Economic Index that best suits your needs. • Terminal Index – This is for Beef farmers that want a bull to breed cattle for live trade or finishing. • Replacement Index – This is for Beef farmers that want a bull to breed their own Replacement females with. • Dairy Beef Index – This is for Dairy farmers that are looking for a beef bull to use in their dairy herd (due in 2015). • The ‘Key Profit Traits’ section gives extra detail on the figures that make up these Overall Economic Indexes. • Remember to look at the ‘Reliability %’ figures at all times.
3. Look at the Calving Difficulty % figure • This shows the % of calvings that are expected to be difficult or require veterinary assistance. • The ‘Calving Difficulty %’ figure must be compared against breed average figures (both within & across breed). • Again, always look at the ‘Reliability %’ figure when assessing a bull’s breeding figures.
• Maternal Progeny Traits: – This is an indication of the profitability of progeny that the daughter’s of a bull will produce for economically important traits. - Maternal Progeny Traits: Calving Difficulty, Gestation, Mortality, Docility, Feed Intake, Carcass Weight, Conformation & Fat.
• Maternal Cow Traits: – This is an indication of the performance of a Bull’s daughter’s for important maternal traits that they express themselves. - Maternal Cow Traits: Milk, Calving Interval, Survival, Age at 1st Calving, Maternal Calving, Heifer & Cow Feed Intake, Docility & Cull Cow Weight.
The ‘Replacement Index’ is split in two so as to clearly show the strengths & weaknesses of a bull’s daughters:
Reliability % - Explained Reliability % Range Comment Bull Type Explanation 0-20% Low Young Bull €uro-Stars mostly based on those of the bull's Parents & Grandparents. 20-50% Low-Medium Young Bull €uro-Stars influenced by the Bull's own Liveweight & Linear Score data. 50-90% Medium-High AI Sire/Stockbull €uro-Stars increasingly affected by the bull's progeny performances > 90% High AI Sire €uro-Stars dominated by the bull's progeny performances Reliability % is an indication as to how confident ICBF can be about the genetic evaluations for a particular bull. Lots of progeny performance recorded (weighed etc) alongside lots of other animals, across large numbers of herds is what increases a Bull’s reliability % figure. Any Young Bull that has not yet sired a calf will not have a reliability % figure greater than 50%.
Calving Difficulty %: • It is important that farmers concentrate on the actual ‘Calving Difficulty %’ figure. • No €uro-Stars are published for ‘Calving Difficulty %’ as the impression that the €uro-Stars were giving of a bull’s calving difficulty was a lot more severe than what his actual calving difficulty percentage figure was saying. • This bull for example has a ‘calving difficulty %’ breeding value of ‘2.60%’ This means that approximately 2.6 calves out of every 100 will result in a difficult calving. The average for the Angus breed is 2.18% so he is only slightly above breed average within the Angus breed and compared to the average calving difficulty figure for all beef breeds (5.04%), he is an easy calving bull.
Top 50%
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3.5 Stars
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2.5 Stars
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5 Stars
€uro-Stars - Explained
€uro-Star Catalogue Page –
Beef HerdPlus
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