Intake, Digestibility, Milk Yield and Indicators of the Metabolic Status of Native Ewes Fed Supplemented Diet Under Grazing System

Abstract

This study aimed to evaluate the intake, digestibility, milk yield and indicators of the metabolic status of native lactating ewes supplemented under grazing system. In the present study 28 lactating ewes were selected: 14 Morada Nova (MN) and 14 Santa Inês (SI), distributed in a completely randomized experimental design, with a 2x2x2 factorial arrangement of two breeds, two supplementation levels and two experimental periods. Blood samples were collected from lambing to 70 days of lactation, with 14 days interval. Laboratory analyses consisted in determining serum glucose, triglycerides, cholesterol, urea and creatinine. Concentrate intake (g/day) during the lactation differed (P<0.05) between breeds. Total dry matter intake of ewes was affected (P<0.05) by breed and treatment. Morada Nova ewes presented lower intake than SI due to their smaller size. Serum glucose, triglycerides, cholesterol, urea and creatinine differed between breeds (P<0.05) with greater levels in SI ewes compared with MN. Concentrate supplementation did not affect (P>0.05) the serum levels of these metabolites. Indicators of the metabolic status were not affected by concentrate supplementation, which was effective for the maintenance of normal serum concentrations. However, these values differ between breeds within the permissible standards, indicating a high adaptation to postpartum.