Abstract

This study was conducted to compare the effects of season on some hematological and biochemical parameters in ewes with subclinical mastitis and healthy ewes. A total of 1192 milk and blood samples were collected from ewes between February and April (791 samples in spring), August and October (401 samples in summer). California Mastitis Test (CMT), milk culture, hematologic and serum biochemical parameters were obtained from the medical records. Samples which were positive by bacterial culture and CMT as were deemed to have glands with subclinical mastitis (SCM). The prevalence of subclinical mastitis in our study was around 12% (in one year). Of 144 (18.2%) and 47 (11.72%) positive samples in CMT, 134 (16.94%) and 44 (10.97%) samples were positive for bacterial culture in spring and summer, respectively. Comparison of results of hematological and serum biochemical parameters in ewes with SCM and healthy ewes in spring and summer showed that WBC counts, total protein concentrations and plasma fibrinogen in both groups of ewes were significantly higher in spring than summer (P˂0.05). The results of the present study indicated that when interpreting hematological and serum biochemical parameters in ewes with SCM should be consider the effect of season on these parameters.