Dynamics of milk leukocytes in response to intramammary infusion of amoxicillin plus sulbactam during bovine subclinical mastitis

The therapeutic potential of amoxicillin plus sulbactam and its effect on dynamics of milk leukocytes in bovine sub clinical mastitis were investigated in this study. Therapeutic efficacy was measured by somatic cell count and total bacterial count of the milk, whereas, the dynamics of milk leukocytes were assessed by measuring phagocytosis, hydrogen peroxide production, myeloperoxidase and lactoperoxidase enzyme levels in the milk leukocytes. Forty-five crossbred cows were randomly divided into three equal groups. Group I consisting of 15 cows served as healthy control, whereas 30 cows (sub clinical mastitis) were randomly divided into Groups II and III on the basis of positive reactions in the California Mastitis Test. Group II cows received 300mg of amoxicillin plus sulbactam twice daily for three days and Group III received sterile 5 ml phosphate buffer saline (pH 7.4) for three days. Both treatments were administered via the intramammary route. Observations were made up to 15 days after initiation of treatment. The results revealed a pronounced drop in somatic cell count and total bacterial count, whereas significant (P < 0.05) enhancement of phagocytic activity (42.20%), hydrogen peroxide production (29.46%), myeloperoxidase (49.27%) and lactoperoxidase (147.10%) enzyme levels in the milk leukocytes in Group II cows during post treatment periods were observed. Such changes were statistically non-significant in Group III cows. The results of the present study indicate that intramammary use of amoxicillin plus sulbactam augments the bactericidal function of milk leukocytes during bovine sub clinical mastitis and demonstrate the strong therapeutic potential against bovine subclinical mastitis.