Colostrum - Early Health Protection
With Lasting Results

Table of Contents

Calf Immunity

At birth, a calf has a poorly developed immune system which is not ready to actively produce protective antibodies in response to disease challenge or vaccination. In addition, no maternal antibodies are present in the new born's blood stream since they cannot cross the placenta during pregnancy1. For the several months before the calf has developed its own active immunity, it must rely on the passive transfer of immunity through the dam's colostrum (first milk) for disease resistance.

Colostrum is rich in the antibodies that provide the calf with protection against infectious diseases. Antibodies, or immunoglobulins (Ig), are proteins that identify pathogens in the calf and promote their destruction. There are three types of Ig in the colostrum of cattle. Cow colostrum contains about 70-80% IgG, 10-15% IgM, and 10-15% IgA.

IgG and IgM identify and inactivate the microorganisms that have entered the blood. IgA attaches to the membranes that line many organs, such as the intestine, and prevents pathogens from attaching and causing disease.

The ability of a calf to absorb antibodies from colostrum drops rapidly over the first few hours of life (Table 1.). By 24 hours of age, the ability to absorb immunoglobulins is nearly non existent. Calves that have not received any colostrum within 12 hours of birth are unlikely to be able to obtain enough antibodies to provide adequate health protection. A study of 45 beef herds in Quebec reported in 2003 found that 19% of the newborn calves had not received adequate passive transfer of immunity from their dams2.


Table 1. The effect of time on colostrum feeding on total immunoglobulin absorption in calves
Time of feeding after birth (hours)
Plasma concentration 24 hours after feeding (mg/ml)
Absorption %

Source: Selk3

Colostrum is also important as the first source of nutrients after birth. "First milk" colostrum is the highest in both antibodies and nutrients. Colostrum that is taken later from the cow decreases in both antibodies and nutrients (Table 2).

Table 2. Typical analysis of colostrum, transitional milk and whole milk
Milking Number
Transitional Milk
Whole Milk
Total solids, %
Fat, %
Protein*, %
Lactose, %
Antibodies, %
Minerals, %
Vitamin A, ug/dl

Source: Davis and Drackley4

Reduced Health Problems and Death Losses

For years, studies have typically suggested that the goal is to provide enough colostrum to result in minimum serum blood IgG levels greater than 10 mg/ml. Failure of passive transfer (FPT) in calves is often defined as a blood IgG level of less than 10 mg/ml at 24 to 48 hours after birth. In support of this recommendation, the results of a 1992 US national survey showed that the mortality rates for calves with low antibody levels (less than 10 grams per liter) were more than twice that of calves with higher levels (Figure 1)

Figure 1. Survival of Calves with Adequate and Inadequate Immunoglobulin Concentrations in Blood Serum

graph showing the percentage of calves surviving is greater when the amount of immunoglobulin in the blood is higher

Source: USDA National Animal Health Monitoring System, 19925

Recently reported research looked the health response of calves with much higher levels of IgG5. The 3 year study, published in 2006, of 1,568 crossbred beef calves in a Nebraska herd found that calves with serum IgG1 concentrations less than 24 mg/ml were 1.6 times more likely to become ill before weaning and 2.7 times as likely to die before weaning as calves with higher serum IgG1 concentrations.

Increased Weaning Weights

A study of 244 Herford and Angus calves at the University of Georgia in 2001 found that calves with higher serum IgG levels at 1 day of age had significantly higher weaning weights than calves with lower IgG levels6. Calves were classified based on their level serum IgG concentrations.

Calves in the group with higher serum IgG (over 16 mg/ml) had a 205 day weaning weight that was 64 pounds heavier than the calves in the group of calves with low IgG levels (below 4mg/ml serum IgG). The calves identified as the middle group with serum IgG levels of 4-16 g/l. had a weaning weight 31 pounds greater than the calves with low IgG levels.

Table 3. Antibody concentrations affects on weaning performance
Blood Serum IgG (mg/ml)
< 4
> 16
Weaning weight increase at 205 days
+ 31 lb
+ 64 lb

Source: Vann and Baker6

Storing Colostrum

Colostrum can be refrigerated at 2oC (36oF) for up to a week or frozen for up to year at 20oC. Avoid frost free freezers.

Warm the colostrum slowly in water or with care in microwave. Avoid hot spots Recent research at the University of Minnesota found that colostrum can be heated to 60oC (140oF) without damaging the antibodies in colostrum.7 However, when the colostrum was heated to 63oC (145oF), the antibodies were reduced by 34%.

Save colostrum for calves only if the cow or heifer meets these criteria:

  • Healthy
  • No mastitis
  • Has not leaked milk
  • No bloody milk
  • Cow has been in the herd for at least 45 days

While high quality colostrum is always the preferred option, colostrum supplements can be valuable tools to increase calf immunity when colostrum supplies are limited. Six colostrum supplements are currently registered for use in Canada. Colostrum supplements can be used to increase the amount of IgG fed to calves when no source of quality colostrum is available, but supplements cannot replace high quality colostrum.


  1. Roy, J.H.B., 1990, The Calf, Volume 1, Management and Health, Butterworths
  2. Filteau V., É Bouchard, G Fecteau, L. Dutil, and D. DuTremblay, Health status and risk factors associated with failure of passive transfer of immunity in newborn beef calves in Québec, Can Vet J. 2003 November; 44(11): 907-913
  3. Selk, G.E., Disease Protection for Baby Calves, F-3358, Oklahoma Cooperative Extension Service
  4. Davis, C.L, and J.K. Drackley, 1998, The Development, Nutrition and Management of the Young Calf, Iowa University State Press
  5. Dewell, R.D., L.L. Hungerford, J.E. Keen, W.W. Laegreid, D.D. Griffin, G.P. Rupp, and D.M. Grotelueschen, 2006, Association of neonatal serum immunoglobulin G1 concentration with health and performance in beef calves., J. American Veterinary Medical Association. 228(6):914-921
  6. Vann, R.C. and J. F. Baker, 2001, Calf serum IgG concentrations affects weaning performance. J. Animal Science. Vol. 79, Suppl. 1, 223-224
  7. McMartin, S., S. Godden, L. Metzger, J. Feirtag, R. Bey, J. Stabel, S. Goyal, J Fetrow, S. Wells, and H. Chester-Jones, 2006, Heat Treatment of Bovine Colostrum. I: Effects of Temperature on Viscosity and Immunoglobulin G Level, J. Dairy Science. 89:2110-2118


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