A.K. DANGANISH KOUL2024-08-162024-08-162023https://krishikosh.egranth.ac.in/handle/1/5810213271Mastitis, an inflammatory condition of the mammary gland and is classified as clinical or subclinical depending on the visibility of the effects of inflammation of the mammary gland. The present study was undertaken to study the total and differential milk cell counts and udder surface temperature in subclinical and clinical mastitis in both indigenous and cross bred cows. A total of 72 cows were selected from Livestock Research Center (LRC), ICAR- NDRI, Karnal and divided into two groups, 36 indigenous (Sahiwal) and 36 crossbred (Karan Fries) cows, and further subdivided into three groups viz., healthy (n=12), subclinical (n=12) and clinical mastitis (n=12) according to their somatic cell count (SCC) and California mastitis test (CMT). Milk from each cow was collected hygienically and evaluated for milk composition, SCC, and DLC. DLC was done by two methods, first by manual microscopic method and then by flowcytometry method by using specific antibodies. Macrophage and lymphocyte percentages decreased with increasing milk SCC, while neutrophil percentages increased during subclinical and clinical mastitis in both the breeds when DLC was done by manual microscopic method. Similar results were observed for neutrophils and macrophages percentage when it was done using flow cytometric method. However, for lymphocytes, two cells i.e., CD4 T helper cells and CD8 cytotoxic cells were evaluated by flowcytometric method. CD4 T helper cells and CD8 cytotoxic cells increased significantly from healthy to sub clinical cases and they decreased from sub clinical to clinical cases in both group of animals but not significantly. Also, ratio of neutrophil to macrophage (N:M) helps in better understanding of mastitis. Udder health was also found to be correlated with udder surface temperature as per objective of this study. It was observed that udder surface temperature increased significantly from healthy to sub clinical to clinical cases in both the group of the animals. It was also observed that with increasing SCC i.e., with increasing udder infection, udder surface temperature increased. This study indicated that DLC by flow cytometric technique and udder surface temperature can give a vivid picture of the condition of udder health.EnglishThesis