Heat Treating Bovine Colostrum

Abstract

The syndesmochorial placenta of the bovine prevents transmission of Ig in utero and calves are born agammaglobulinemic. Consequently, ingestion and absorption of adequate amounts of colostral Ig are essential for establishing immunity until the calf's own immune system becomes completely functional. A successful colostrum management program should consider age of calf at first feeding, volume of colostrum administered, and Ig concentration of the colostrum ingested. In addition, because several bacterial pathogens can be transmitted in colostrum, heat treating fresh colostrum has been suggested as a method for reducing or eliminating those pathogens. Early studies on pasteurization of bovine colostrum using the same times and temperatures recommended for milk reduced or eliminated important bacterial pathogens; however, this process reduced Ig concentration and increased viscosity. More recent studies using lower temperatures have shown no reduction in colostral Ig concentration or fluidity and have concluded that heat-treated colostrum can be successfully fed on commercial dairy farms without interfering with passive transfer of immunity in calves. The objective of this paper is to present a comprehensive review of the literature of bovine colostrum pasteurization, including the importance of colostrum for the neonate, IgG absorption, and effects of pasteurization on bacterial load, viscosity, and IgG concentration.