Efeito da sobrealimentação com fontes de proteína de diferentes degradabilidades sobre a ovulação em ovelhas Santa Inês

Abstract

This study aimed at evaluating plasma concentration of urea nitrogen, the number of ovulations and the diameter of ovulatory follicle of Santa Ines ewes submitted to flushing with sources of protein with different ruminal degradabilities. Forty-four estrus-synchronized ewes were fed isoprotein diets composed of soybean meal (n = 24) or corn gluten meal and cottonseed meal (n = 20) for 28 days before ovulation. Animals were distributed in a block design in which the blocks were formed by three score ranges of body condition score. Body weight and body condition score gains, body weight and body condition score on the 28th experimental day, urea nitrogen plasma concentration, number of ovulations and diameter of the ovulatory follicle did not differ among ewes submitted to flushing with soybean meal or with corn gluten and cottonseed meal. Ewes under soybean meal flushing showed higher urea nitrogen plasma concentration on days seven and 14 and lower concentration on the 28th day when compared to those fed corn gluten and cottonseed meal (day vs. diet interaction). The supply of one diet with lower content of ruminal degradable protein does not reduce urea nitrogen plasma concentration neither alters the number of ovulations and diameter of ovulatory follicle.