Perfil metabólico de cordeiros em pastejo submetidos a diferentes ambientes e suplementações alimentares no Semi-Árido Paraibano.

Abstract

Mineral and protein profiles of 27 uncastrated Santa Inês lambs were studied under different levels of concentrate (C) supplementation (0, 1.0 and 1.5% of total body weight supplementation, in a dry matter basis) and environmental conditions (no shadow = SOL, and natural shadow = SNA and artificial shadow = SAR by a 80%-solar radiation reduction factor polyethylene screen). The animals had daily access to the buffel-enriched (Cenchrus ciliaris L cv. Bioela) pasture from 7:00 to 16:00 h, when they were gathered back to collective stalls, one for each supplementation level, with 1.0 m2/animal, provided with feeders and water. The collected data were analyzed according to a completely random design with 3x3 (three environments and three supplementation levels) factorial treatments and three replications. When necessary, treatment means were compared by the Duncan’s test at the significance level of 5%. Phosphorus (P) concentrations in blood serum were 7.08 ±0.30, 6.80±0.17 and 7.67±0.21 mg/dL for the diets with 0, 1.0 and 1.5% of supplementation, respectively. No significant environmental effect was observed on P concentration, and the overall mean value was 7.18±0.25 mg/dL. The 1%- supplemented animals and kept in SOL environmental conditions showed significantly (p < 0.05) lower Ca levels in blood serum than the animals kept in SAR conditions. The animals kept in SAR conditions presented significantly (p < 0.05) higher Mg levels in blood serum than the animals kept in SOL conditions under the 1.5%-supplement diet. The mean urea serum values of the animals submitted to zero, 1.0 and 1.5%-supplement diets were 37.89, 40.67 and 55.05 mg/dL; for creatinin the values were 1.95, 1.85 and 1.81 mg/ml; and for total proteins the values were 4.45, 4.72, and 4.63 g/dL. Under SOL, SNA and SAR conditions, these values were, respectively, 39.56, 44.70 and 49.37 mg/dL for urea, 1.87, 1.92, and 1.81 mg/dL for creatinin, and 4.63, 4.62, and 4.55 g/dL for total proteins. It was observed that the different treatments affected significantly (p < 0.05) urea concentration in blood serum. Among the lambs supplemented at the 1.5% level, serum albumin concentration was significantly (p < 0.05) higher in those kept under SNA than those kept under SOL conditions. The study of the metabolic profile is an important tool for monitoring lamb production systems.