Use of recombinant bovine somatotropin (rbST) in dairy buffaloes II: energy and mineral metabolism

ABSTRACT The aim was to evaluate the influence of recombinant bovine somatotropin (rbST) on the energy and mineral metabolism of buffaloes between 63 - 154 days in milk. Twenty-two buffaloes distributed in two experimental groups were used: Group rbST (n= 11) - application of 500mg of rbST every 14 days; Control Group (n= 11) - no rbST. Every seven days, blood samples were taken to determine the biochemical profile, and milk production and body condition score were measured. The averages of the variables for rbST and Control groups were, respectively: milk yield (MY) - 6.44kg vs. 6.68kg; body condition score (BCS) - 3.51 vs 3.57 (1-5); glucose - 70.58 vs. 64.81mg/dL (P = 0.0003); cholesterol - 132.38 vs. 133.40mg/dL; triglycerides -29.18 vs. 28.32mg/dL; total protein - 8.57 vs. 8.75g/dL; albumin - 3.47 vs 3.60g/dL; urea - 32.46 vs 33.86mg/dL; creatinine - 1.27 vs 1.39mg/dL; calcium - 10.25 vs. 10.73mg/dL; phosphorus - 5.76 vs 5.62mg/dL; and magnesium - 3.70 vs 3.70mg/dL. Use of 500mg rbST influenced glucose metabolism, but did not modify the MY, BCS and the levels of the other metabolic parameters studied.