Colostrum
A practical guide for correct colostrum feeding in calves M贸nica Espada Aguirre Luis Miguel Ferrer Mayayo Juan Jos茅 Ramos Ant贸n
The veterinary publishing company Production animals
bovine
Colostrum
A practical guide for correct colostrum feeding in calves Technical specifications Authors: Mónica Espada Aguirre,
Juan José Ramos Antón, Luis Miguel Ferrer Mayayo.
Format: 11 x 20 cm. Number of pages: 60 Number of images: 100 Binding: paperback, wire-o. ISBN spanish edition: 978-84-92569-61-8. Year: 2011 The authors’ experience backs up one of the most practical and easy-to-use books about colostrum. This guidebook tries to answer the basic questions related to the daily activity of vets, cattle producers and technicians, ranging over issues such as birth and cow, but featuring a special focus on the need for an adequate administration of colostrums to calves, a key to minimize the neonatal calf mortality.
Aimed at veterinary surgeons, students, teachers and other professionals in the veterinary sector.
Centro Empresarial El Trovador, planta 8, oficina I - Plaza Antonio Beltrán Martínez, 1 • 50002 Zaragoza - España Tel.: +34 976 461 480 • Fax: +34 976 423 000 • pedidos@grupoasis.com • Grupo Asís Biomedia, S.L.
The veterinary publishing company
Colostrum
A practical guide for correct colostrum feeding in calves
TABLE OF CONTENTS 1. Introduction 2. The cow The udder
3. Birth and management of the calf The labour and the foetus Preparation for calving Stages of calving Attention and assistance during calving When is it advisable to intervene during calving?
Assessment of the newborn calf Management of the newborn calf How to proceed with the newborn calf?
4. Colostrum and colostrum intake What are the components of colostrum? How much colostrum does a calf need to take? When does the calf need to take the colostrum? Are all colostrum the same? Immunologic quality How can the quality of colostrum be determined?
Hygienic quality
5. Alternatives to maternal colostrum: substitutes and supplements Fresh or preserved colostrum Commercial products
6. Feeding of the calf Transition from colostrum to milk
7. Bibliography
Centro Empresarial El Trovador, planta 8, oficina I - Plaza Antonio Beltrán Martínez, 1 • 50002 Zaragoza - España Tel.: +34 976 461 480 • Fax: +34 976 423 000 • pedidos@grupoasis.com • Grupo Asís Biomedia, S.L.
10
COLOSTRUM. A practical guide for correct colostrum feeding in calves
Introduction
11
Mortality in pre-weaned calves in relation to farm size (% of calves that survive the first 48 hours of life). (Source: NAHMS, 2007).
Figure 1. The main causes of mortality in calves are due to dystocia, diarrhoea and pneumonia.
Figure 2. In small farms, the attention given to the calves is combined with other tasks.
amongst the main predisposing factors are inadequate passive transfer of immunity and lack of attention given to the newborns. Poor colostrum management is the direct cause of 11% of deaths in pre-weaned calves. Forty per cent of those deaths in that time period have been attributed to failure of passive transfer of immunity (NAHMS 1993, NAHMS 2007). This results in losses for the farm. In a study conducted in the United States it was found that poor colostrum intake generates eight U.S. dollars in veterinary costs per calf. Also losses due to mortality, reduced growth, workload, etc. must be added (Faber, et al., 2005, Quigley, 2003).
Figure 3. A heifer's first calf has a higher mortality rate. In general, heifers have higher rates of dystocia, which reduces the vitality of the calf and increases the time it takes for it to stand for the first time. Heifers also produce lower quality colostrum.
Type of operation
Mortality (%)
Small (< 100)
8.3
Medium (100-499)
9.1
Large (> 500 cows)
6.5
Average
7.8
Unfortunately, many operations in Spain do not keep mortality records. However, they enable the problem and origin of calf deaths to be analysed and solved by taking the appropriate measures. These records should include: the total of calf deaths to calculate the mortality rate, the timing and circumstances of death, the time of year to discover seasonal effects and the possible aetiologies, etc.
Figure 4. In large operations specialised personnel manage the calves closely which results in a lower mortality rate.
are Diarrhoeal processes of es one of the major caus le ultip mortality in calves. M eir th factors are involved in n entio appearance, but prev the in is the key to success ers. sord fight against these di
Figure 5. Some studies have demonstrated that mortality rates are lower when women manage and care for the calves.
10
COLOSTRUM. A practical guide for correct colostrum feeding in calves
Introduction
11
Mortality in pre-weaned calves in relation to farm size (% of calves that survive the first 48 hours of life). (Source: NAHMS, 2007).
Figure 1. The main causes of mortality in calves are due to dystocia, diarrhoea and pneumonia.
Figure 2. In small farms, the attention given to the calves is combined with other tasks.
amongst the main predisposing factors are inadequate passive transfer of immunity and lack of attention given to the newborns. Poor colostrum management is the direct cause of 11% of deaths in pre-weaned calves. Forty per cent of those deaths in that time period have been attributed to failure of passive transfer of immunity (NAHMS 1993, NAHMS 2007). This results in losses for the farm. In a study conducted in the United States it was found that poor colostrum intake generates eight U.S. dollars in veterinary costs per calf. Also losses due to mortality, reduced growth, workload, etc. must be added (Faber, et al., 2005, Quigley, 2003).
Figure 3. A heifer's first calf has a higher mortality rate. In general, heifers have higher rates of dystocia, which reduces the vitality of the calf and increases the time it takes for it to stand for the first time. Heifers also produce lower quality colostrum.
Type of operation
Mortality (%)
Small (< 100)
8.3
Medium (100-499)
9.1
Large (> 500 cows)
6.5
Average
7.8
Unfortunately, many operations in Spain do not keep mortality records. However, they enable the problem and origin of calf deaths to be analysed and solved by taking the appropriate measures. These records should include: the total of calf deaths to calculate the mortality rate, the timing and circumstances of death, the time of year to discover seasonal effects and the possible aetiologies, etc.
Figure 4. In large operations specialised personnel manage the calves closely which results in a lower mortality rate.
are Diarrhoeal processes of es one of the major caus le ultip mortality in calves. M eir th factors are involved in n entio appearance, but prev the in is the key to success ers. sord fight against these di
Figure 5. Some studies have demonstrated that mortality rates are lower when women manage and care for the calves.
16
COLOSTRUM. A practical guide for correct colostrum feeding in calves
The udder The udder should be clean and healthy at all times to prevent infection and thereby achieve an adequate production of colostrum and milk. A dry-off period allows for a good recovery. The state of health of the cow and especially of its udder is crucial for milk production. It especially effects the quantity and quality of colostrum production, as well as the possibility of the dam to nurse the newborn.
Figure 9. Udder morphology varies depending on the breed.
Figure 10. Acute mastitis. Mastitis is painful and it may cause the dam to prevent the calf from nursing.
Figure 11. Oversized or diverted teats may hinder the calf from sucking.
Figure 12. Udder oedema due to parturition. It may extend both cranially and caudally and remain for several days after calving.
The cow
17
Colostrum is the first secretion of the mammary gland following parturition. Its production begins around three to six weeks before, but in the last two weeks the concentration of antibodies and other substances increases markedly. A premature delivery or an excessively short dry-off period lowers the levels of immunoglobulins in the colostrum. In general a 60-day dry-off time is recommended, however it seems that a 30-40 day dry-off time for cows with good condition and management does not adversely affect colostrum quality. Udder health is vital and a routine examination should be made after delivery, especially in beef cows. Milking ensures that dairy cows are monitored daily. The dairy calf's feed does not depend on udder health (it receives artificial feeding).
Figure 13. Colostrum is thick, yellowish, with pH 6 and high protein and cell content. Post-delivery udder secretion showing abnormal coloration, watery, cloudy and/or with clots, etc. indicates clinical mastitis.
Figure 14. A pink or red-tinged colostrum indicates the presence of blood; in some animals this appears after calving but is not due to any disorder, however it may also be related to mastitis, leptospirosis, poisoning, etc.
16
COLOSTRUM. A practical guide for correct colostrum feeding in calves
The udder The udder should be clean and healthy at all times to prevent infection and thereby achieve an adequate production of colostrum and milk. A dry-off period allows for a good recovery. The state of health of the cow and especially of its udder is crucial for milk production. It especially effects the quantity and quality of colostrum production, as well as the possibility of the dam to nurse the newborn.
Figure 9. Udder morphology varies depending on the breed.
Figure 10. Acute mastitis. Mastitis is painful and it may cause the dam to prevent the calf from nursing.
Figure 11. Oversized or diverted teats may hinder the calf from sucking.
Figure 12. Udder oedema due to parturition. It may extend both cranially and caudally and remain for several days after calving.
The cow
17
Colostrum is the first secretion of the mammary gland following parturition. Its production begins around three to six weeks before, but in the last two weeks the concentration of antibodies and other substances increases markedly. A premature delivery or an excessively short dry-off period lowers the levels of immunoglobulins in the colostrum. In general a 60-day dry-off time is recommended, however it seems that a 30-40 day dry-off time for cows with good condition and management does not adversely affect colostrum quality. Udder health is vital and a routine examination should be made after delivery, especially in beef cows. Milking ensures that dairy cows are monitored daily. The dairy calf's feed does not depend on udder health (it receives artificial feeding).
Figure 13. Colostrum is thick, yellowish, with pH 6 and high protein and cell content. Post-delivery udder secretion showing abnormal coloration, watery, cloudy and/or with clots, etc. indicates clinical mastitis.
Figure 14. A pink or red-tinged colostrum indicates the presence of blood; in some animals this appears after calving but is not due to any disorder, however it may also be related to mastitis, leptospirosis, poisoning, etc.
26
COLOSTRUM. A practical guide for correct colostrum feeding in calves
Birth and management of the calf
27
Assessment of the newborn calf Time taken to stand up: (60-158 minutes with the mother/60-228 minutes without the mother). Time taken to suckle on the mother: 60-120 minutes. Body temperature: 37-38ยบC during the first hour, and 38.5-39.5ยบC afterwards.
Assessment of a weak calf Difficult breathing or apnoea (more than two minutes). Slow jugular filling time. Slow in attaining sternal recumbence and/or pulling in its limbs (more than 30 minutes). Figure 12. Foetal hypoxia in the uterus may cause meconium to be released into the amniotic fluid. This is evident because the calf is meconium-stained at birth, including brownish liquid in the nostrils. In these cases it is important to clean the respiratory passages and supply an adequate level of ventilation.
Takes a long time or is unable to stand. No suck or poor suck reflex, weak and coughs.
Figure 13. When attention is not given to the birth the survival of the calf depends on its vitality or capability to stand up. The sooner it stands the better. By standing it avoids being trampled on and reduces contact with a dirty floor. It also hastens the ingestion of colostrum.
The most critical moment for the neonate occurs during its expulsion when the umbilical cord is compressed and ruptured and the placenta starts to detach. These changes can evidently have an impact on hypoxia (levels of oxygen in the blood) and metabolic acidosis.
Pathogenesis of hypoxia and acidosis in a calf DYSTOCIA - FOETUS IN THE CANAL
Uterine contractions
Lesser blood flow
Assessment of a premature animal Age at birth (Holstein: normal gestation is 278-282 days). Low weight at birth (Holstein: normal weight 35-45kg).
The placenta detaches Rupture of the umbilical cord
Greater gas exchange (placenta)
Weak or unable to remain standing. Visible weakness, folded ears, soft lips, short or little hair, etc.
HYPOXIA ACIDOSIS
26
COLOSTRUM. A practical guide for correct colostrum feeding in calves
Birth and management of the calf
27
Assessment of the newborn calf Time taken to stand up: (60-158 minutes with the mother/60-228 minutes without the mother). Time taken to suckle on the mother: 60-120 minutes. Body temperature: 37-38ยบC during the first hour, and 38.5-39.5ยบC afterwards.
Assessment of a weak calf Difficult breathing or apnoea (more than two minutes). Slow jugular filling time. Slow in attaining sternal recumbence and/or pulling in its limbs (more than 30 minutes). Figure 12. Foetal hypoxia in the uterus may cause meconium to be released into the amniotic fluid. This is evident because the calf is meconium-stained at birth, including brownish liquid in the nostrils. In these cases it is important to clean the respiratory passages and supply an adequate level of ventilation.
Takes a long time or is unable to stand. No suck or poor suck reflex, weak and coughs.
Figure 13. When attention is not given to the birth the survival of the calf depends on its vitality or capability to stand up. The sooner it stands the better. By standing it avoids being trampled on and reduces contact with a dirty floor. It also hastens the ingestion of colostrum.
The most critical moment for the neonate occurs during its expulsion when the umbilical cord is compressed and ruptured and the placenta starts to detach. These changes can evidently have an impact on hypoxia (levels of oxygen in the blood) and metabolic acidosis.
Pathogenesis of hypoxia and acidosis in a calf DYSTOCIA - FOETUS IN THE CANAL
Uterine contractions
Lesser blood flow
Assessment of a premature animal Age at birth (Holstein: normal gestation is 278-282 days). Low weight at birth (Holstein: normal weight 35-45kg).
The placenta detaches Rupture of the umbilical cord
Greater gas exchange (placenta)
Weak or unable to remain standing. Visible weakness, folded ears, soft lips, short or little hair, etc.
HYPOXIA ACIDOSIS
COLOSTRUM. A practical guide for correct colostrum feeding in calves
How much colostrum should a calf receive? During the first 12 hours of life the calf's intestine has the maximum capacity to absorb the defences passed on by its mother through her colostrum. This is the best â&#x20AC;&#x153;medicineâ&#x20AC;? that exists to prevent nearly all the diseases which may affect calves in the first days of their lives. Once the calf is born there are 24 hours for the animal to receive all the colostrum it needs. The first question is whether the calf is to be nursed by its mother or to be fed by artificial lactation. In the first instance, assurance is needed that the dam's udder is in perfect conditions to feed the calf. If there is any doubt, then the colostrum must be administered via a bucket or a nipple bottle or through an oesophageal feeder. In the second instance, if the calf is going to be fed by artificial lactation, it is not a good idea to allow the calf to suckle the dam for colostrum, as this creates a bond which must be broken in a few hours. A calf of approximately 40kg body weight should ingest about six litres of colostrum during the first day of life. Two litres should be ingested as soon as possible postpartum, two more in the next 8-10 hours and another two within 24 hours. However, as already mentioned, the quantity of colostrum to
Colostrum and colostrum feeding
uivalent A calf can ingest the eqweight of 10-15% of its body its life. during the first day of st 5% If possible it should inge of its life. before the second hour
% mortality
36
37
16 14 12 10 8 6 4 2 0
0.9-1.8 1.8-3.6 3.6-4.5 Colostrum ingested at 12 hours (kg)
be supplied depends on various factors, mainly the quality of the colostrum and the calf's body weight.
Figure 5. Mortality (%) in calves between the first week of life and six months old, according to the quantity of colostrum ingested at 12 hours of life. (Source: Clemson University).
Figure 6. Calves should ingest sufficient colostrum to reach an optimum passive immunity level. Colostrum ingestion is essential to prevent diarrhoea and pneumonia during the first stage of life.
8 7 Kg of colostrum
6
Concentration of Ab
Colostrum/feed (5% weight) Colostrum/24 hours (15% weight)
5 4 3
Passive immunity (colostrum) Active immunity
2 1 0
0 25
30
35 40 Weight at birth (kg)
45
50
Figure 4. The amount of colostrum a calf can ingest in one feeding (5%) and during the first day of life (15%) according to its body weight.
1
8
14
21 28 Age in days
35
42
48
Figure 7. At the same time that the antibodies (Ab) of the colostrum are disappearing, the calf's immune system is increasing the production of its own antibodies (Ab) until the system is working completely. If the colostral immunoglobulin supply is low, the risk of infection remains high.
COLOSTRUM. A practical guide for correct colostrum feeding in calves
How much colostrum should a calf receive? During the first 12 hours of life the calf's intestine has the maximum capacity to absorb the defences passed on by its mother through her colostrum. This is the best â&#x20AC;&#x153;medicineâ&#x20AC;? that exists to prevent nearly all the diseases which may affect calves in the first days of their lives. Once the calf is born there are 24 hours for the animal to receive all the colostrum it needs. The first question is whether the calf is to be nursed by its mother or to be fed by artificial lactation. In the first instance, assurance is needed that the dam's udder is in perfect conditions to feed the calf. If there is any doubt, then the colostrum must be administered via a bucket or a nipple bottle or through an oesophageal feeder. In the second instance, if the calf is going to be fed by artificial lactation, it is not a good idea to allow the calf to suckle the dam for colostrum, as this creates a bond which must be broken in a few hours. A calf of approximately 40kg body weight should ingest about six litres of colostrum during the first day of life. Two litres should be ingested as soon as possible postpartum, two more in the next 8-10 hours and another two within 24 hours. However, as already mentioned, the quantity of colostrum to
Colostrum and colostrum feeding
uivalent A calf can ingest the eqweight of 10-15% of its body its life. during the first day of st 5% If possible it should inge of its life. before the second hour
% mortality
36
37
16 14 12 10 8 6 4 2 0
0.9-1.8 1.8-3.6 3.6-4.5 Colostrum ingested at 12 hours (kg)
be supplied depends on various factors, mainly the quality of the colostrum and the calf's body weight.
Figure 5. Mortality (%) in calves between the first week of life and six months old, according to the quantity of colostrum ingested at 12 hours of life. (Source: Clemson University).
Figure 6. Calves should ingest sufficient colostrum to reach an optimum passive immunity level. Colostrum ingestion is essential to prevent diarrhoea and pneumonia during the first stage of life.
8 7 Kg of colostrum
6
Concentration of Ab
Colostrum/feed (5% weight) Colostrum/24 hours (15% weight)
5 4 3
Passive immunity (colostrum) Active immunity
2 1 0
0 25
30
35 40 Weight at birth (kg)
45
50
Figure 4. The amount of colostrum a calf can ingest in one feeding (5%) and during the first day of life (15%) according to its body weight.
1
8
14
21 28 Age in days
35
42
48
Figure 7. At the same time that the antibodies (Ab) of the colostrum are disappearing, the calf's immune system is increasing the production of its own antibodies (Ab) until the system is working completely. If the colostral immunoglobulin supply is low, the risk of infection remains high.
48
COLOSTRUM. A practical guide for correct colostrum feeding in calves
Fresh or preserved colostrum A reserve supply of colostrum should be maintained according to the farm's needs. This should be of proven quality and perfectly preserved; either refrigerated at 1-2ºC or frozen at -18 to -20ºC. The best alternative to replace maternal colostrum is to use colostrum from another healthy cow. It is preferable that the cow is from the same operation, at least third-parity, reaches labour with a good body condition score of 3-4, has been dry for more than 40 days and a production of less than 8.5 kilos at first milking. Under these conditions the colostrum is very likely to be of high quality; however it should always be tested. Each farm must have a reserve supply of colostrum. The quantity will depend upon the number of births per month. Its preservation must be done under adequate conditions to avoid any future problems. Colostrum can be preserved by different procedures: Refrigeration at 1-2ºC is the best procedure to preserve colostrum. It can be preserved for a week without altering its quality. However, it is worthwhile ensuring that the true temperature of the refrigerator is 1-2ºC (never more than 4ºC) and
Alternatives to the mother's colostrum: replacers and supplements
49
e The best alternativrum to maternal colost the is colostrum from same farm. Figure 2. The thawing process requires great care to avoid immunoglobulin denaturation. This should take place in a warm water bath at a temperature inferior to 50ºC. Once thawed the colostrum should be used immediately.
that the colostrum was obtained under guaranteed hygienic conditions. Freezing at –18 or –20ºC destroys the cells but does not affect the immunoglobulin concentration. Freezing is ideal in plastic bags or bottles of 0.5 to 2 litres, as they are easy to handle. A smaller container is quicker to freeze and thaw. To thaw, place the container in a warm water bath at a tem-
Figure 1. Freezing colostrum in 1-2 litre containers is a good method of preservation. Figure 3. Thawing in a microwave oven should be controlled carefully, as the heat distribution is not homogeneous and can deteriorate the quality of the colostrum.
48
COLOSTRUM. A practical guide for correct colostrum feeding in calves
Fresh or preserved colostrum A reserve supply of colostrum should be maintained according to the farm's needs. This should be of proven quality and perfectly preserved; either refrigerated at 1-2ºC or frozen at -18 to -20ºC. The best alternative to replace maternal colostrum is to use colostrum from another healthy cow. It is preferable that the cow is from the same operation, at least third-parity, reaches labour with a good body condition score of 3-4, has been dry for more than 40 days and a production of less than 8.5 kilos at first milking. Under these conditions the colostrum is very likely to be of high quality; however it should always be tested. Each farm must have a reserve supply of colostrum. The quantity will depend upon the number of births per month. Its preservation must be done under adequate conditions to avoid any future problems. Colostrum can be preserved by different procedures: Refrigeration at 1-2ºC is the best procedure to preserve colostrum. It can be preserved for a week without altering its quality. However, it is worthwhile ensuring that the true temperature of the refrigerator is 1-2ºC (never more than 4ºC) and
Alternatives to the mother's colostrum: replacers and supplements
49
e The best alternativrum to maternal colost the is colostrum from same farm. Figure 2. The thawing process requires great care to avoid immunoglobulin denaturation. This should take place in a warm water bath at a temperature inferior to 50ºC. Once thawed the colostrum should be used immediately.
that the colostrum was obtained under guaranteed hygienic conditions. Freezing at –18 or –20ºC destroys the cells but does not affect the immunoglobulin concentration. Freezing is ideal in plastic bags or bottles of 0.5 to 2 litres, as they are easy to handle. A smaller container is quicker to freeze and thaw. To thaw, place the container in a warm water bath at a tem-
Figure 1. Freezing colostrum in 1-2 litre containers is a good method of preservation. Figure 3. Thawing in a microwave oven should be controlled carefully, as the heat distribution is not homogeneous and can deteriorate the quality of the colostrum.
56
COLOSTRUM. A practical guide for correct colostrum feeding in calves
Figure 6. Water is essential when feeding the animals; therefore animals should have high quality water freely available.
Figure 7. Any animal that appears to be ill or injured should receive immediate treatment, and should be placed in an appropriate, comfortable area with dry bedding.
e high Calf starter feeds ar with quality food, preparedulating the objective of stim to develop consumption, helping d achieving the rumen papillae an soon a functional rumen as as possible.
Figure 8. The calves should not remain in individual pens for more than eight weeks.
Feeding the calf
Decalogue for a good production of calves
1 2
The udder must be clean and healthy to achieve an adequate production of colostrum and then be able to feed the calf.
3 4
Calving must be observed and attended to correctly to prevent perinatal mortality.
5
The management of a newborn calf should follow a clearly defined protocol to minimise the risk of diseases.
6
The calf needs to ingest between 10-15% of its body weight in colostrum within the first 24 hours of its life.
7
Use first milking colostrum from healthy cows which are at least third-parity and with a milk production inferior to 8.5 kilos.
8
The farm should have a reserve supply of proven quality colostrum which is perfectly preserved.
9
The handling and preservation of the colostrum must provide maximum guarantees of hygiene without altering its quality.
10 Figure 9. The animals should be inspected at least twice a day with adequate lighting.
A correctly fed dam, with a drying-off period of no less than 40 days, which reaches calving with an optimal body condition of 3.25.
Help during calving and care to the newborn must be provided by persons with knowledge, experience and capability.
Commercial products may be very useful as supplements to prevent failure in colostrum feeding management.
57
56
COLOSTRUM. A practical guide for correct colostrum feeding in calves
Figure 6. Water is essential when feeding the animals; therefore animals should have high quality water freely available.
Figure 7. Any animal that appears to be ill or injured should receive immediate treatment, and should be placed in an appropriate, comfortable area with dry bedding.
e high Calf starter feeds ar with quality food, preparedulating the objective of stim to develop consumption, helping d achieving the rumen papillae an soon a functional rumen as as possible.
Figure 8. The calves should not remain in individual pens for more than eight weeks.
Feeding the calf
Decalogue for a good production of calves
1 2
The udder must be clean and healthy to achieve an adequate production of colostrum and then be able to feed the calf.
3 4
Calving must be observed and attended to correctly to prevent perinatal mortality.
5
The management of a newborn calf should follow a clearly defined protocol to minimise the risk of diseases.
6
The calf needs to ingest between 10-15% of its body weight in colostrum within the first 24 hours of its life.
7
Use first milking colostrum from healthy cows which are at least third-parity and with a milk production inferior to 8.5 kilos.
8
The farm should have a reserve supply of proven quality colostrum which is perfectly preserved.
9
The handling and preservation of the colostrum must provide maximum guarantees of hygiene without altering its quality.
10 Figure 9. The animals should be inspected at least twice a day with adequate lighting.
A correctly fed dam, with a drying-off period of no less than 40 days, which reaches calving with an optimal body condition of 3.25.
Help during calving and care to the newborn must be provided by persons with knowledge, experience and capability.
Commercial products may be very useful as supplements to prevent failure in colostrum feeding management.
57