Dietary Strategies to Improve the Health of Dairy Calves

It is well documented that dairy calves are extremely susceptible to enteric diseases and mortality during the first few weeks of life. The latest reports from the USDA’s National Animal Health and Monitoring System (NAHMS, 1993; 1996; 2007) report that the national mortality rate of heifer calves from 48 hours of life to weaning is approximately 7.8 to 10.8%. Producer perceived records indicate that scours account for 56.5 to 60.5% of all pre-weaned deaths. Approximately 1⁄4 of all pre-weaned calves are therapeutically treated for scours, and the major causes of death from scours are due either to dehydration or to pathogen access to the blood causing septicemia. There is a high incidence of respiratory disease among dairy calves and it is the main contributor to high death losses, 1.8%, after weaning (NAHMS, 2007). The high incidences of disease indicate that we have much to learn about improving gastrointestinal disease resistance among pre-weaned calves. Colostrum management, how much and the composition of fluid fed, the use of various additives such as prebiotics, probiotics, and proteins from hyper-immunized egg or plasma proteins, and housing can all influence the health of pre-weaned dairy calves. In addition, there are few data that indicate that early life nutrition can have long-term impacts on leukocyte responses and disease resistance (Ballou, 2012; Ballou et al., JDS In Press; Sharon and Ballou, unpublished). This is an exciting area of research that needs to be addressed further.