Abstract #W45

# W45
Effects of porcine plasma or combined sodium butyrate and Bacillus subtilis on growth and health of dairy calves.
D. Wood*1, R. Blome1, A. Keunen2, D. Renaud3, J. Campbell4, J. Crenshaw4, 1Animix LLC, Juneau, WI, 2Mapleview Agri Ltd, Palmerston, ON, Canada, 3Population Medicine, University of Guelph, Guelph, ON, Canada, 4APC Inc, Ankeny, IA.

The objective of this study was to evaluate the health and performance effects of incorporating 2 common feed additives, Bacillus subtilis (1.3 million cfu/g) and 70% sodium butyrate at 2kg/MT (FA), or spray dried porcine plasma (SDPP) at 5% of the milk replacer formula (MR). Holstein male calves (n = 158) were randomly assigned to receive one of 3 formulas containing SDPP, FA, or a control group with no feed additives or non-milk proteins. Calves were housed individually until weaning at d 49, then commingled into consecutive groups of 5 until d 78. MR was formulated with 26% crude protein (CP) and 17% fat and fed at 0.7 kg powder / d in 2 feedings for 5 weeks followed by 0.45 kg of MR powder / d over a 2-week weaning period. Calf starter (18% CP) was fed for 21 d followed by a mixed corn and supplement (18.1% CP) ration for the remainder of the study. For the first 28 d following arrival, calves were scored for fecal consistency on a scale of 0 to 3 with 0 being normal manure and 3 meaning watery feces. Calves were observed daily for symptoms of respiratory disease. Body weights were recorded at arrival, 49, and 78. A Cox proportion hazard model was built to evaluate the impact of treatment groups on the risk of morbidity, and mortality over the growing period, whereas a mixed linear regression model was built to evaluate the effect on average daily gain. To evaluate the effect of treatment group on fecal score, a generalized linear model with a logit link and binomial family was used. There was no difference between the groups with respect to body weight (P = 0.56), or level of serum total protein (P = 0.48) measured at arrival. Calves in the FA group had an increased risk of mortality (P = 0.02) when compared with the control group. SDPP fed calves had a reduction in the number of days with a fecal score of 3 (P = 0.03). There were no significant differences between groups with respect to treatment for diarrhea, respiratory disease, or average daily gain. This study suggests that feeding plasma in milk replacer may help reduce the severity of diarrhea, whereas, adding the FA could result in a higher risk of mortality.

Key Words: calf, health, growth