Comparison of somatic cell count, California mastitis test, chloride test and rennet coagulation time with bacterial culture examination to detect subclinical mastitis in riverine buffalo (Bubalus bubalis)

Abstract

The study investigates the etio-prevalence of bubaline subclinical mastitis (SCM) with reference to relationship between somatic cell counts (SCC), California mastitis test (CMT), rennet coagulation time (RCT) and chloride test with bacterial cultural examination. Each test was conducted by standardized protocol. The prevalence of subclinical mastitis (SCM), latent infected quarters and non-specific infected quarters were found to be 17.83, 2.89 and 3.06%, respectively, when partitioned on the basis of International Dairy Federation criteria for SCC. Staphylococcus spp. (44.70%) and Streptococcus spp. (34.20%) were the most prevalent etiological agents isolated in this study. The mean values of SCC and RCT were compared separately in healthy and SCM milk infected by different etiological agents by Duncan multiple range test. Mean comparison for these values for healthy and SCM milk was done by t-test. The elevation recorded for SCC and RCT was highly significant (p<0.01) irrespective of the bacterial agents causing SCM. After calculating the percent sensitivity, specificity and accuracy, predictive values and likelihood ratios, it can be accomplished that SCC was mostly in agreement with bacterial culture examination. It is recommended that it is better to cross match the result of SCC with RCT and CMT. Chloride test is not suggested to diagnose SCM in riverine buffaloes. Key words: Bacterial culture, buffalo, California mastitis test, chloride test, rennet coagulation time, somatic cell count, subclinical mastitis.