Composição corporal e exigências de macro e microelementos minerais para bovinos sindi

Abstract

The present study had as objective to determine net and dietary requirements of macromineral of Sindi cattle, through physical and chemical analysis of all tissue body (direct method) and section between 9 and 11ª ribs (indirect method). Forty bulls with average weight 296.65 ± 21.33 kg and mean age of 21 ± 1.5 months were used in the experiment. Four animals of each method were slaughtered at the beginning of the experiment to compose the reference group, the remaining animals were distributed, within each method, randomly, into four food restriction levels (0.0, 15.0, 30.0 and 45.0%), making a scheme 2x4 factorial. At the end of the experiment all animals were slaughtered, and the gastrointestinal tract of each animal was emptied, washed and weighed, and this weight was added to the organs and other animal’s body parts (carcass, head, leather, tail, feet and blood) for empty body weight (EBW) determination. These parts, as well as tissues section between 9 and 11ª ribs, were analyzed for determination of Ca, P, Na, K and Mg. The net requirements of Cu, Fe, Zn and Mn for gain ranged from 5.37 to 4.99; 48.91 to 52.21; 57.62 to 85.09 and from 0.061 to 0.075 mg kg EBW-1 , respectively, in the direct method and from 41,83 a 42,27 e 27,84 a 28,02 mgKg EBW-1 for the Fe and Zn, respectively, in the indirect method, as the BW increased from 250 to 400 kg. The total dietary macrominerals requirements of Ca, P, Na, K and Mg were obtained 57.75; 14.63; 3.94; 39.67 and 8.38 g d-1 to the direct method and 35.09; 16.45; 4.26; 40.02 and 8.41 g d-1 for animals with a live weight of 400 kg. In conclusion, the direct method was the most appropriate to determine the requirements of macromineral and micromineral Sindhi cattle.