EXIGÊNCIAS LÍQUIDAS PARA RETENÇÃO DE PROTEÍNA E ENERGIA EM OVINOS NO CLIMA SEMIÁRIDO. PATOS-PB: UFCG

Net requirements for protein and energy retention in sheep in a semi-arid climate.

Abstract

The objective of this work was to estimate the nutritional requirements of energy and protein for weight gain of Santa Inês sheep with different genders, males and females, kept in confinement. The experiment was carried out at the Research Center for the semiarid region (NUPEÁRIDO), Federal University of Campina Grande (UFCG), Patos-PB. Twenty-four 80±5 day-old sheep were used, including 12 males and 12 females, with an average body weight (BW) of 15 Kg, distributed in completely randomized blocks with three treatments (0%, 25% and 50% of food restriction). The diet consisted of elephant grass hay and concentrate with a ratio of 50:50 (roughage:concentrate). Initially, six animals were slaughtered and used as reference to estimate empty body weight (EBW) and initial body composition. The animals were confined for 58 days, receiving the diet in individual stalls. The body composition per Kg varied from 285.98 to 320.16 g of dry matter, 41.60 to 46.96 g of mineral matter, 160.44 to 175.71 g of protein and 1.49 to 1.80 Kcal of energy. It was observed that the proteinconcentration in the animal body increased from 152 to 182 g/Kg when the weight of the animals increased from 15 to 30 Kg. In the present study, the amount of energy/Kg of empty body weight gain ranged from 2.21 to 3.39 Mcal/ Kg. Net protein and energy requirements were similar for both males and females and increased with increasing body weight. The estimate of protein requirements was similar to that presented in the National Research Council(NRC), while energy was 27% lower.