Blood metabolites and circulating mineral profile of lambs maintained under intensive feeding and grazing with supplementation

Ten each of Malpura weaner lambs were maintained under intensive feeding (G1) and grazing with concentrate supplementation @ 1.5% of BW (G2) for a period of 90 days. Along with the growth perfonnance, blood biochemical and mineral profile were assessed periodically by collecting blood at 0, 1, 2, and 3 months of the study. Initial weight was lower in G2 while finishing weights were similar in the two groups hence total gain and ADG were higher (P<0.01) in G2 (9.0 kg; 106 g) than G1 (7.9 kg; 92 g). Blood glucose level in both the groups was higher (P<0.01) at the beginning of the experiment, which gradually decreased, with continuation of the study. Total protein, albumin and globulin concentrations ranged from 9.0–10.8, 4.2–4.8 and 4.2–6.1 g %, respectively and were similar in the two groups and sampling periods. Blood urea N was lower (P<0.01) in G2 (21.5 mg %) than G1 (28.2 mg %) receiving 1% urea in their composite feed lot ration. The concentrations of serum Ca, Cu, Zn and Mn were similar in the two groups and the periods of samplings averaging to 143.7, 2.1, 1.8 and 0.09 mg/l respectively. The K concentration was however higher (P<0.01) in lambs under grazing with supplementation (309.4 mg/l) compared to intensive feeding (275.5 mg/l).

It was concluded that total gain and ADG were higher under protocol of grazing with supplementation than intensive feeding. The blood metabolites and minerals of the lambs under the two systems of grazing management were within normal range of variation whereas blood urea N was higher in intensively fed lambs due to extra urea supplementation. Additionally potassium content was higher under protocol of grazing with supplementation than intensive feeding.