INTERDEPENDENCE AND DISTRIBUTION OF SUBCLINICAL MASTITIS AND INTRA-MAMMARY INFECTION AMONG UDDER QUARTERS IN JERSEY CROSSBRED COWS

Abstract- The study was aimed to investigate the interdependence and distribution of subclinical mastitis (SCM) and intra-mammary infection (IMI) among udder quarters in Jersey crossbred cows reared in hot-humid environment. Total 366 quarter wise morning milk samples were collected aseptically after performing California mastitis test (CMT) at milking byre itself to evaluate the incidence of infection in experimental cows maintained at cattle yard, ICAR- National Dairy Research Institute, Eastern Regional Station, Kalyani, West Bengal and subjected to microscopic method of somatic cell count to estimate the level of intra-mammary infection. The overall quarter wise incidence rate of IMI and SCM in Jersey crossbred cows was 54.65% and overall arithmetical mean (±SE) of test day SCC (logarithmic) was 5.377 ± 0.039. The percent incidence of SCM in different quarter was 51.14, 59.79, 48.94 and 58.70 in left fore (LF), left hind (LH), right fore (RF) and right hind (RH) quarters respectively. The higher incidence was observed in hind (59.23%) as comparison to fore (50%) quarters while incidence was found to be slightly more distributed in left (55.56%) than right side (53.76%) quarters. Further, the analysis of variance showed that there was no significant effect of quarter on the log 10SCC level. However, the mean Log 10SCC was found higher for hind and right quarters numerically only. The trend of subclinical mastitis incidence obtained in the current study point out that, the rate of incidence of SCM in different quarters was not similar and was higher in hind quarters and therefore, hind and right side quarter required attention during different udder health management programmes.