<b>Body composition and nutritional requirements in calcium and phosphorus of Santa Inês sheep on the feed in the semi-arid</b> - DOI: 10.4025/actascianimsci.v30i1.3609

Abstract

This work aimed to evaluate the body composition and the calcium and phosphorus nutritional requirements of Santa Inês lambs under rangeland conditions in the semi-arid region of Brazil. Thirty-two castrated lambs between 3 to 4months old were used, with an initial mean body weight of 15.8 kg ± 1.4 kg. Of these, eight were slaughtered in the beginning of the experiment to provide the initial body composition (“Reference Animals” of the comparative slaughter method). The other animals were divided randomly in groups of three, as the lambs reached 15 kg. The three levels of food supplementation were randomly assigned to the lambs in each group (block). When the first animal in each group reached 30 kg, the whole group was slaughtered. The animals were kept in native rangeland enriched with buffelgrass (Cenchrus ciliaris L. cv. Biloela). Their diets were supplemented daily with three levels of concentrate mixture (0.0, 1.0 and 1.5% of their body weight). The estimated values of body composition, in g kg^-1 of empty body weight, ranged from 14.91 g to 17.11 g for Ca, and from 5.33 g to 6.08 g for P. The net requirements gain of 15-to-30-kg lambs, in g kg^-1 gained in live body weight, ranged from 9.4 mg to 10.8 mg for Ca, and from 3.76 mg to 3.89 mg for P.