highly significantP value ≤0.05
Seasonal variation, as shown in Figure 4 , in this study, had a highly significant effect on the infection rate ( P value ≤0.05); at winter season, calves showed the highest significant infection rate (11.24%), followed by spring (7.9%), and the lowest infection rate was prevailed in the summer season (3.4%); the P value was (0.021), significant 95%, and the odd ratio (1.09) and confidence interval between (0.987–1.198), for the age group as shown in Figure 5 ; the highest significant infection rate ( P value ≤0.05) was found in suckling calves from birth to one month old (8.2%), followed by calves aged from 1 to 6 months (7.2%).