Six crossbred goats in their 2nd or 3rd lactation, were administered bromocryptine at 5 mg/day during early lactation of 15-20 days (period I) and thereafter again at an interval of 13 days, bromocryptine was given for 5 days (period II). Blood samples were collected befor (-5, -4, -3, -2, -1) during (1, 2, 3, 4, 5) and after (+!, +2, +3, +4, +5) administration of bromocryptine in both the periods of study. In period I, administration of bromocryptine resulted in a decrease in milk yield to the extent of 16.8% in comparison to before treatment, and 28.5% after the cessation of treatment. The glucose content of blood increased (p<0.01) as the milk yields did not change in spite of a decline in prolactin level, perhaps the effect of previous treatment was prolonged. A decline in protein and lactose content of milk after bromocryptine treatment in both the periods of study, when prolactin level also declined suggests a role of prolactin in protein synthesis and also a depressing effect on lactose synthesis.
Keywords :
Prolactin;Blood Metabolites;Milk Yield and Composition;Bromocryptine;Early Lactation;Goats