SUPPLEMENTATION BOVINE SOMATOTROPIN EFFECTS ON MILK PRODUCTION, LEVELS OF METABOLITES AND HORMONE METABOLISM ON LACTATION HOLSTEIN COWS KEPT IN THE TROPICAL HIGHLANDS
Elvia Hernawan, Wasmen Manalu, S. Hamdani Nasution, Nastiti Kusumorini
The use of recombinant somatotropin (bST) recommended to increase milk production has not been used widely in Indonesia so it is the necessary to study somatotropin supplementation effects on milk production, metabolite and hormone metabolism. A total of 24 Holstein cows in lactation maintained in the tropical highlands has been used in this study. The study by using randomized complete block design with 3x2 factorial pattern should have been elaborated. The first factor of BST 3 level mentioned with was composed of non bST or control group and daily bST(36 mg/head/day) and biweekly bST (500mg/head/14 days). Bovine somatotropin was injected by intramuscular. The second factor is the feeding consisting of 2 levels. The first level is usually food consume or standard feed (feed from Research Center) and the second is a standard feed plus 25% concentrate. The parameters measured include the production of milk, glucose, triglycerides, blood urea nitrogen, cortisol, T4, T3 in the blood, and body condition score. There is interaction between supplementation of somatotropin and the addition of concentrated 25% on milk production and a change of body weight. Somatotropin supplementation followed by the usual food consumption can increase milk production by 17-26%, but somatotropin supplementation did not affect significantly the levels of metabolites and hormone metabolism and body condition score.
Key words: recombinant somatotropin, milk production, metabolite, hormone metabolism