The Effect of Blood and Milk Serum Zinc Concentration on Milk Somatic Cell Count in Dairy Cows.

The objective of this study was to evaluate the effect of blood and milk zinc concentration on milk somatic cell count and occurrence of subclinical mastitis cases. The study was performed on thirty Holstein cows approximate same body weight, ages 3 to 5 years, with equally milk production. Blood samples were taken after morning milking from the caudal vein. Milk samples were taken before morning milking. Zinc concentration was determined from blood and milk by inductively coupled plasma mass spectrometry. 37.67% cows have zinc blood serum concentration below 7μmol/l, and 63.33% cows have zinc blood serum concentration higher then 13μmol/l. Also 30% cows have somatic cell count lower then 400.000/ml which indicate absence of subclinical mastitis, but 70% cows have somatic cell count higher than 400.000/ml which indicate subclinical mastitis. Results indicate that cows with level of zinc in blood serum higher then 13µmol/l have lower somatic cell count. Cows with lower zinc blood serum concentration then 7μmol/l have high somatic cell count and high incidence of subclinical mastitis. According to results in this research there is no significant effect of milk serum zinc concentration on somatic cell count in dairy cows. [ABSTRACT FROM AUTHOR]