3.5. Association of C. parvum Infection with Diarrhea Occurrence as Indicated by Univariate and Multivariate Analyses
In the univariate analysis of data, C. parvum -positive calves had a significantly higher occurrence of diarrhea (odds ratio = 3.20,P = 0.002, Table 5), especially watery diarrhea (odds ratio = 14.78, P = 0.000). There was no correlation betweenCryptosporidium infection and occurrence of moderate diarrhea. In addition, neonatal calves were more likely to have watery diarrhea (odds ratio = 34.12, P = 0.001, Table 5) and moderate diarrhea (odds ratio = 3.09, P = 0.000, Table 5) than older animals. Further analysis using the multivariate model showed that C. parvuminfection was the only species associated with the occurrence of diarrhea (odds ratio = 2.98, P = 0.016, Table 5), especially watery diarrhea (odds ratio = 11.19, P = 0.000, Table 5). In addition, age was an important risk factor associated with the occurrence of watery diarrhea (odds ratio = 40.00, P = 0.001, Table 5) and moderate diarrhea (odds ratio = 2.91, P = 0.001, Table 5) in these animals.