Este estudo avaliou o efeito de suplementos alimentares com diferentes níveis de proteína sobre a resposta reprodutiva e metabólica de ovelhas durante o período de monta. Quarenta e uma ovelhas foram suplementadas durante 43 dias com proteína em quantidade para satisfazer 1,0 (dieta I; n = 14), 1,7 (dieta II; n = 13) e 2,1 (dieta III; n = 14) vezes as exigências de manutenção. O consumo de matéria seca (MS) foi superior (P < 0,01) na dieta III quando comparada com as dietas I e II. As sobras foram menores nas dietas II e III (P < 0,05) quando comparada à dieta I. O consumo de matéria orgânica (MO), proteína bruta (PB) e extrato estéreo (EE) foram superiores na dieta III, porém a ingestão de NDF e ADF foi maior na dieta I (P < 0,05). Na dieta III foi observada uma maior frequência de fêmeas montadas (P < 0,05). A taxa de prolificidade e gemelaridade foi maior em ovelhas da dieta II (P < 0,05). Verificou-se um maior peso ao nascimento de cordeiros (P < 0,05) na dieta III. Os níveis de progesterona medidos após o acasalamento foram afetados pelas dietas II e III (P < 0,05). Em conclusão, a suplementação de ovelhas com nível intermediário de proteína melhora sua resposta reprodutiva.

This study evaluated the effect of food supplements with different levels of protein on reproductive and metabolic response of ewes during the mating period. Forty-one ewes were supplemented during 43 days with amount protein to meet 1.0 (diet I; n = 14), 1.7 (diet II; n = 13) and 2.1 (diet III; n = 14) times the maintenance requirements. Dry matter (DM) intake was higher (P < 0.01) in diet III when compared to diets I and II. Orts were lesser in diets II and III (P < 0.05) when compared to diet I. Intake of organic matter (OM), crude protein (CP) and ether extract (EE) was higher in diet III (P < 0.05), but NDF and ADF intake was superior in diet I (P < 0.05). In diet III, a higher frequency of female mated was observed (P < 0.05). The prolificity and twinning rate was higher in ewes of diet II (P < 0.05). Greater birth weight of lambs (P < 0.05) was verified in diet III. The progesterone levels were affected by diets II and III (P < 0.05). In conclusion, the supplementation of ewes with intermediate level of protein improves their reproductive response.

The objective of the present study was to evaluate the effects of supplementation with detoxified castor meal (DCM) in the diet of ewes during pregnancy, partum, and post-partum on the weight development of their offspring and at slaughter. The study included 56 ewes with synchronized estrus that were naturally mated. At the beginning of pregnancy and in post-partum, hepatic and renal function-related parameters and progesterone levels were measured. At slaughter, the proximate composition and fatty acid profile were determined in the loin of ewes. There was no effect of diet on reproductive response after estrus synchronization. At the beginning of pregnancy, albumin and creatinine levels were lower in the DCM group. Supplementation with DCM did not alter the weight or body condition of ewes at partum. However, at weaning, the DCM group showed a higher loin-eye area (LEA) in relation to the group fed diets without detoxified castor meal (WDCM). At partum, as well as at weaning, the offspring of the ewes supplemented with DCM had a larger LEA than the WDCM group. In post-partum, levels of glucose, urea, protein, and cholesterol were lower in the DCM group. The return to cyclicity was similar in both groups, with an average of 47 days after partum. At slaughter, neither anatomical and carcass components nor the results of the proximate analysis were affected by the type of diet, except for an increase in heptadecanoic acid in the DCM group. Supplementation with detoxified castor meal in the diet of ewes does not affect lambing, pregnancy, prolificacy, return to cyclicity, milk production, blood biochemical parameters, or carcass characteristics.