Effect of Nutritional Plane on Health and Performance in Dairy Calves after Experimental Infection with Cryptosporidium parvum
Keywords:energy requirements, neonatal, dairy calf, milk replacer, nutritional plane, conventional, C. parvum, protozoan, Cryptosporidium parvum
Neonatal dairy calf maintenance energy requirements are approximately 1.6 Meal metabolizable energy (ME)/d at thermoneutral temperatures. Historically used milk replacer feeding regimens (e.g. 2 quarts ofreconstituted solids twice per day) provide approximately 2.2 Meal ME/d. Considering the abundance of environmental and pathogenic challenges faced by neonatal calves, these conventional feeding programs provide little energy reserves for maintaining body temperature, mounting immune responses, and growing at expected rates of 1.1 to 2.0 lb/d (0.5 to 0.9 kg/d). Cryptosporidium parvum, an enteric protozoan, is an almost ubiquitous infectious stressor of neonatal dairy calves. Infection by this organism is difficult to prevent and treat. As it is a zoonotic parasite, a few oocysts may infect and cause disease in naive people, and infections are a severe health risk in the immunocompromised. The objective of this study was to evaluate the effect of conventional nutritional plane versus a higher nutritional plane on the health and performance of dairy calves after experimental infection with C. parvum.