Growth, haematological and biochemical responses of growing lambs injected

Abstract

Physiological and productive responses to recombinant bovine somatotropin (rbST) injection and calcium soap of fatty acids (CSFA) supplementation were studied in post-weaning male Rahmani lambs. Male lambs (n = 20) of similar initial body weight (27.9 kg) and age (162 d) were divided randomly into four equal groups. The first was fed the injected with 100 mg of rbST biweekly; the third (basal diet and served as control; the second (GH) was CSFA) was supplemented with 50 g/d of CSFA and the fourth (GH + CSFA) was injected with 100 mg of rbST biweekly plus 50 g/d of CSFA. Treatments increased the average daily gain and final body weight. Concentration of insulin-like growth factor-1 (IGF-1) in lambs treated with (GH) and (GH + CSFA) was higher than that of CSFA and control groups. Haematological parameters (RBC, WBC, and haemoglobin concentrations) did not change. Animals injected with rbST had higher serum total protein than other treated groups and controls. Control lambs showed the least serum albumin concentration. Injection of rbST and supplementation of CSFA increased serum glucose in treated lambs compared to controls. Serum urea concentration was not affected by injection of GH, while CSFA supplementation decreased serum urea concentration compared to the control. Serum triglycerides concentration decreased in rbST-injected lambs than other treatment groups. Lambs supplemented with CSFA only or combined with rbST had higher concentration of serum cholesterol than control or rbST-injected lambs. The results of the present study suggest that rbST and CSFA may increase the average daily gain and improve the physiological status of growing lambs.