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Alvaro Garcia

Most colostrum is readily absorbed during the first hours of life, when the intestinal epithelium is still open to the passage of larger molecules (e.g., IgG, IgA, and IgM). Aside from its well-known effects on providing passive immunity through immunoglobulins, colostrum is an excellent source of nutrients with a much higher concentration compared with that of milk.

In addition, colostrum adds to what has been termed ‘metabolic programming’, which begins in-utero and continues after birth. Milk-borne bioactive factors transferred from the mother in early life, play a critical role in programming later life events through cellular signaling mechanisms, immunity, and growth and differentiation of the digestive tract.

Alvaro Garcia

It has been well documented that pre-weaned calves raised during summer have reduced gains. The reasons are multifactorial and include pre- and postnatal heat stress, flies, and wet bedding result of rainfall.  Heat stress seems to be the main culprit however, with mechanisms to increase cooling (i.e. respiratory and cutaneous evaporative cooling) triggered when ambient temperatures exceed 20 °C. These mechanisms use energy and result in more energy for maintenance and less energy available for growth.

Fernando Diaz

Newborn calves are immunodeficient. Colostrum provides them immunity, but it also can be a potential source of pathogen microorganism such as Mycobacterium avium ssp. paratuberculosis (Johne’s disease), Mycoplasma spp., Escherichia coli, and Salmonella spp. For this reason, heat treating colostrum to reduce or eliminate pathogens is a common practice in the dairy industry. However, heat treatment may affect colostrum immunoglobulin G concentration.