Nonsteroidal anti-inflammatory drug therapy for neonatal calf diarrhea complex: Effects on calf performance

Todd, C. G.; Millman, S. T.; McKnight, D. R.; Duffield, T. F.; Leslie, K. E.

The second factor that likely influenced the incidence of neonatal calf diarrhea complex was heightened exposure to C. parvum. At the time this study was conducted, the incidence of neonatal calf diarrhea, and in particular, the occurrence of diarrhea associated with C. parvum, was increased throughout Ontario (Trotz-Williams et al., 2005 , 2008b . In 2002, the within-herd prevalence for C. parvum shedding by calves on 51 Ontario dairy farms was between 0 and 70% (Trotz-Williams et al., 2005) . In 2003, the withinherd prevalence for C. parvum shedding by calves on 11 Ontario dairy farms was between 35 and 100% (Trotz-Williams et al., 2007) . In the summer and fall of 2004, the within-herd prevalence for C. parvum shedding by calves on 119 Ontario dairy farms was between 0 and 80% (Trotz-Williams et al., 2008b) . Moreover, this research group found that the odds of diarrhea were 5.3 times greater among calves shedding C. parvum as compared with nonshedding calves (Trotz-Williams et al., 2007) . Thus, it is evident that C. parvum infection and diarrhea are common among preweaned dairy calves in Ontario, and can be a widespread problem on a given farm. The authors of this study had previously acquired calves from the 3 source farms used in this research. As such, at the onset of the study, the authors were familiar with the typical rates of neonatal diarrhea and C. parvum isolation in calves from these farms and had expected the incidence of diarrhea to be increased. Fecal samples were collected from the calves, and it was determined that C. parvum was the primary agent of infection, but rotavirus and coronavirus were also isolated from the feces of some of the calves (Todd, 2007) . Thus, the increased incidence of naturally occur- ring diarrhea among the calves may have been due to C. parvum being spread between calves and throughout the study environment.