An overview of calf diarrhea - infectious etiology, diagnosis, and intervention

Cho, Yong-il; Yoon, Kyoung-Jin

The bovine placenta does not permit the passive transfer of antibody to the fetus. As a result, the newborn calf does not receive any antibody from the dam and is very susceptible to environmental pathogens. Resistance of the calf to enteric disease is closely related to the timely consumption of high-quality colostrum in sufficient quantities [7] . The neonatal calf should ideally receive 2∼3 L (for beef calves) or 3∼4 L (in dairy calves) of colostrum within the first 6 h after birth [22] . The colostrum contains antibodies, immune cells (neutrophils, macrophages, T cells, and B cells), complements, lactoferrin, insulin-like growth factor-1, transforming growth factor, interferon, and other soluble factors as well as nutrients (sugars and fat-soluble vitamins) [94] . Immunoglobulin G is the primary antibody isotype in bovine colostrum. The quality of colostrum varies based on calving number, nutritional status, and vaccination of the cow [98] . However, calves born to heifers can receive an acceptable level of maternally derived immunity if enough volume of colostrum is ingested within the first 24 h of life [71] . Heifers have a greater likelihood for dystocia, mis-mothering, and poor colostrum production compared to a multiparous cow. Therefore, cow-calf management practices (e.g., calving heifers first and segregation of calves based on birth date) should be considered for reducing the chances of infectious disease development.