Colostrum for dairy calves: importance and best practices

The timely administration of high-quality colostrum to dairy calves is a critical step in dairy calf rearing as it provides calves the energy and protection calves need against pathogens during the neonatal period^1,2. It also contributes to the maturation and development of their gastrointestinal tract³.

Poor colostrum management leads to failed transfer of passive immunity (FTPI) which is associated with lower average daily gain, a greater risk for preweaning morbidity and mortality, and a lower likelihood to reach first insemination and calving^{4, 5}. Despite these well known facts, FTPI remains substantially elevated in many dairy herds, potentially preventing them from achieving good calf health and welfare performances. In a large study in the USA in 2014, FTPI was detected in 12% of calves^6,7, while a recent survey found that 25% of male and female calves in Ontario, Canada, had failed transfer of passive immunity, which is suggestive of inadequate colostrum management⁸.

To achieve successful colostrum management is not an easy task as this requires a series of meticulous steps that must be done following good practices. In this article, we will review current best management practices regarding colostrum to facilitate knowledge dissemination and “raise the bar” in dairy calf health.

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What is colostrum?

Colostrum is the first lacteal secretion of mammals following parturition. It is secreted by mammary epithelial cells prior to parturition and is physically and chemically distinct from regular milk. Colostrum is also sometimes mistaken as transition milk (TM), which, although more nutritive than regular milk, has a different biochemical composition and is produced right after colostrum from milkings 2 to 6⁹.

In the case of dairy cows, colostrum is characterized by a high contents of immunoglobulin G (IgG). It also contains many other bioactive constituents, such as growth factors (mainly IGF-I and IGF-II), and fatty acids (mainly n-3 and n-6 fatty acids). In addition, bovine colostrum is rich in macro and micronutrients (proteins, lipids, carbohydrates, minerals and vitamins) to meet the nutritional and energy requirements of the neonatal calf. Maternal microorganisms are also present and are helpful to establish calf’s microbiota³.

Why is colostrum so essential for a good start in life in dairy calves?

Colostrum is like an “essential starter kit” for neonatal calves¹⁰. It contains nutrients (for energy, thermoregulation), immune cells (for protection), and helpful microorganisms which are crucial for the calf’s health and development, especially in their early days.

Importantly, dairy cows have a specific placenta structure called synepitheliochorial placenta that prevents passage of large molecules such as immunoglobulins to their foetus. Consequently, dairy calves are born agammaglobulinemic or, in other words, with limited defense¹¹.

Although calves do have natural immunity and can develop their acquired immunity over time, the lack of IgG at birth (i.e. colostrum) makes it almost impossible for them to successfully face the challenges of the most common infections such as neonatal diarrhoea and pneumonia (BRD)^1,7.

What are the key rules to follow to maximize its health benefits?

The following “golden rules” of colostrum management are generally acknowledged:

• Hygienically milk healthy cows quickly after calving (≤ 8 h following calving)¹².
• Only use top-quality colostrum (≥50 g of IgG/L; ≥ 22.0% Brix) with low bacterial contamination². Colostrum quality can be determined with a Brix refractometer and only colostrum with ≥22% Brix should be used.
• Excessive microbial contamination of colostrum reduces IgG absorption and causes enteritis². Therefore, hygiene must be strict throughout the entire colostral process. A microbiology of < 100,000 CFU/mL and < 10,000 CFU/mL total coliform count must be always maintained².
• Feed calves 8.5 to 10% of BW of colostrum (300 g of IgG) within 2 hours after birth. Lower volumes or delayed administration increase the FTPI^2,13.
• A second colostrum meal, within 12h after birth, 5 to 7.5% BW, is considered beneficial¹⁴. The aim is to achieve 400 g of IgG administered on the first day of life.
• Continuing to feed transitional milk, or regular milk mixed with colostrum, for 2 to 4 days further reduces the risk of disease and improves calf growth¹⁵.
• If possible, avoid pooling colostrum as the risk of FTPI are more than twice as likely for calves fed pooled colostrum compared to colostrum from individual cows¹⁶. Colostrum mixing decreases the final IgG concentration and increases the risk of disease transmission.
• Pasteurize the colostrum for 30 to 60 minutes at 60 °C in small batches to prevent salmonella, Johne´s disease, mycoplasma, leucosis, or tuberculosis transmission. By doing so, microbiological contamination is also controlled and, therefore, IgG absorption increases¹⁷.
• Freeze the colostrum for preservation and defrost it in a water bath at 40 °C. Colostrum should be refrigerated for no more than 3 days and if not used, frozen for use within the next year¹⁸.
• For good control of the entire TPI process a monitoring program must be implemented.

How to make sure colostrum is properly given?

Without a doubt, the way to check FTPI is by determining the levels of IgG in the blood of the calves. This can be carried out by taking a blood sample from the calves at less than one week old and measuring the IgG or the total protein in serum or, more simply, indirectly by means of a refractometer determining the degrees Brix (⁰Brix).

© AHDB

In recent decades the mortality rates in dairy calves have been greatly reduced. However, morbidity remains high along with everything associated with it, such as the excessive use of antibiotics. For this reason, it has been recently recommended to adjust the previous threshold of 10 g/L of IgG of the past 30 years according to new TPI categories^2,13. These updated numbers should be the new targets for modern dairy farms aimed at reducing further the burden of calfhood diseases.

Table 1. Serum IgG and equivalent total protein and Brix degrees, and percentage of calves for each category
(from Godden et al., 2019² and Lombard et al., 2020¹³).

Closing

There is little doubt about the vital importance of colostrum for the prevention of infectious diseases in dairy calves. Consequently, every effort should be made to reach optimal colostrum feeding in dairy farms. Acknowledgement and implementation of the golden rules of colostrum management are key to “raise the bar” in dairy calves’ health. Veterinarians can certainly contribute by leading the discussions with their farmers on this critical topic.

References

1 Urie NJ, Lombard JE, Shivley CB, Kopral CA, Adams AE, Earleywine TJ, Olson JD, Garry FB. Preweaned heifer management on US dairy operations: Part V. Factors associated with morbidity and mortality in preweaned dairy heifer calves. J Dairy Sci. 2018;101(10):9229-9244.

2 Godden SM, Lombard JE, Woolums AR. Colostrum Management for Dairy Calves. Vet Clin North Am Food Anim Pract. 2019;35(3):535-556.

3 Diddeniya G, Ghaffari MH, Hernandez-Sanabria E, Guan LL, Malmuthuge N. INVITED REVIEW: Impact of Maternal Health and Nutrition on the Microbiome and Immune Development of Neonatal Calves. J Dairy Sci. 2024 May 31:S0022-0302(24)00869-5.

4 Crannell P, Abuelo A. Comparison of calf morbidity, mortality, and future performance across categories of passive immunity: A retrospective cohort study in a dairy herd. J Dairy Sci. 2023 Apr;106(4):2729-2738.

5 Sutter F, Venjakob PL, Heuwieser W, Borchardt S. Association between transfer of passive immunity, health, and performance of female dairy calves from birth to weaning. J Dairy Sci. 2023 Oct;106(10):7043-7055.

6 Shivley CB, Lombard JE, Urie NJ, et al. Preweaned heifer management on US dairy operations: Part II. Factors associated with colostrum quality and passive transfer status of dairy heifer calves. J Dairy Sci. 2018;101:9168–9184.

7 NAHMS (National Animal Health Monitoring System). 2021a. Morbidity and Mortality in U.S Preweaned Dairy Heifer Calves: NAHMS Dairy 2014 Study Calf Component. USDA (United States Department of Agriculture), Fort Collins, CO.

8 Renaud DL, Steele MA, Genore R, Roche SM, Winder CB. Passive immunity and colostrum management practices on Ontario dairy farms and auction facilities: A cross-sectional study. J Dairy Sci. 2020 Sep;103(9):8369-8377.

9. Conneely, M.; Berry, D.P.; Murphy, J.P.; Lorenz, I.; Doherty, M.L.; Kennedy, E. Effect of feeding colostrum at different volumes and subsequent number of transition milk feeds on the serum immunoglobulin G concentration and health status of dairy calves. J. Dairy Sci. 2014, 97, 6991–7000.

10. Silva FG, Silva SR, Pereira AMF, Cerqueira JL, Conceição C. A Comprehensive Review of Bovine Colostrum Components and Selected Aspects Regarding Their Impact on Neonatal Calf Physiology. Animals. 2024; 14(7):1130.

11. Lopez AJ, Heinrichs AJ. Invited review: The importance of colostrum in the newborn dairy calf. J Dairy Sci. 2022;105(4):2733-2749.

12. Westhoff TA, Borchardt S, Mann S. INVITED REVIEW: Nutritional and management factors that influence colostrum production and composition in dairy cows. J Dairy Sci. 2024 Jan 19:S0022-0302(24)00034-1.

13. Lombard JE, Urie N, Garry F, Godden S, et al. Consensus recommendations on calf- and herd-level passive immunity in dairy calves in the United States. J. of Dairy Science. 2020; 103:7611-7624.

14. Abuelo A, Cullens F, Hanes A, Brester JL. Impact of 2 Versus 1 Colostrum Meals on Failure of Transfer of Passive Immunity, Pre-Weaning Morbidity and Mortality, and Performance of Dairy Calves in a Large Dairy Herd. Animals (Basel). 2021 Mar 11;11(3):782. 

15 Pletts S, Pyo J, He S, Haines D, Guan L, Steele M. PSI-19 Effect of extended colostrum feeding on serum IgG in newborn calves. J Anim Sci. 2018 Dec;96(Suppl 3):182.

16. Beam AL, Lombard JE, Kopral CA, Garber LP, Winter AL, Hicks JA, Schlater JL. Prevalence of failure of passive transfer of immunity in newborn heifer calves and associated management practices on US dairy operations. J Dairy Sci. 2009 Aug;92(8):3973-80.

17. Robbers L, Jorritsma R, Nielen M, Koets A. A Scoping Review of On-Farm Colostrum Management Practices for Optimal Transfer of Immunity in Dairy Calves. Front Vet Sci. 2021; 8:668639.

18. Rowntree, J.K. (2023). Colostrum: Day 1 and beyond. American Association of Bovine Practitioners Conference Proceedings.