THE COLOSTRUM COUNSEL - Explaining the Worldwide Efficacy of Natural Colostrum Replacers
A common misconception is that calves should receive colostrum from their own dam or herd to be protective against pathogens present on their own farm. However, certain natural colostrum replacers do in fact provide protection from diseases worldwide and should be considered in any colostrum management program.
A commonly asked question about colostrum replacer products is: How is it that a colostrum product from one country works to protect calves in other countries?
This is a valid question since there is a general belief that the best protection of the calf is obtained when it is fed colostrum from his or her own dam, or from a cow in the same herd. This assumption is based the concept of the development of “herd immunity” which builds on the observation that pathogens re-circulating on a given farm boost immune responses of the animals in that herd. However, this “herd immunity” concept doesn’t guarantee that 100% of the cows on the farm will receive an effective natural-boost through exposure to all infectious agents at the appropriate time to generate high colostrum antibody titers. Therefore, the most important factor to consider is if a particular cow has or has not been exposed to a given calf pathogen prior to parturition. If she has, she will secrete antibodies against that pathogen into her colostrum and that colostrum should provide good protection if fed correctly. If she hasn’t (even if she is the mother) there would be no boost in antibody titers and that colostrum could be deficient in antibodies to that particular pathogen. In testing individual pails of colostrum it is not uncommon to find cows that lack antibodies to one or more of the important pathogens causing disease in calves even though those agents are present on the farm.
In addition, the assumption that the mother’s colostrum is always better is sometimes interpreted as the belief that antibodies present in colostrum from the mother or another cow from the same herd have antibodies to some kind of “private” strain of infectious agent not present in other regions or countries. There is no epidemiological (epizootiological) evidence to support that statement. The common causes of calf morbidity and mortality during the first 3 weeks of life are pneumonias and diarrheas caused by pathogens capable of infecting the respiratory and intestinal mucosal surfaces (Table 1). These pathogens are world-wide in distribution (only absent in countries with pathogen-specific eradication programs) and antibodies against them have broad cross-protection among the isolates from different locations and countries.
|Table 1: Common pathogens causing disease in newborn calves|
Achieve the results
To harvest these long-term milk production benefits, start with a sound colostrum management program. Experts agree that calves should be removed from their dam immediately following birth. This prevents the spread of disease and increase the likelihood that newborns will consume adequate amounts of clean, maternal colostrum or a high quality colostrum replacer.
Among the pathogens listed in the table BVDV shows the most variability, and even then, antigenic similarities between type 1a and type 1b and between type 2a and type 2b BVD viruses are sufficiently high that antibodies to one of types (a or b) provides protection to the other type. In fact all commercially available vaccines used to prevent the disease are formulated using 2 viral strains only (type 1a and 2 a) and they are effective in cows and calves worldwide.
Some natural colostrum replacers are often manufactured by collecting colostrum from thousands dairy cows, effectively eliminating the risk of the absence of protective antibodies against important pathogens that exist when colostrum is sourced from a single donor cow. In addition, considering the worldwide distribution of the above listed pathogens, antibodies to the same pathogen present in colostrum sourced from a different farm even from a different country will provide equal protection to antibodies from the mother/farm. As long as the antibodies are specific to the pathogen and are present in sufficient amounts in the colostrum they will have comparable efficacy.
DVM, MSc, PhD - South America Veterinary Technical Services, The Saskatoon Colostrum Company