Avaliação da biometria testicular, epididimal e de glândulas sexuais acessórias e correlações entre características biométricas e histológicas em carneiros deslanados sprd

• Ano de defesa: 2006
• Autor(a) principal: Martins, Jorge André Matias
• Orientador(a): Campos, Ana Cláudia Nascimento
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Palavras-chave em Português: Avaliação histológica; Mensurações testiculares; Trato reprodutor masculino; Ovinos deslanados; Zootecnia
• Palavras-chave em Inglês: Histological evaluation; Testicular measurements; Correlations; Male reproductive tract; Hairy rams
• Link de acesso: http://www.repositorio.ufc.br/handle/riufc/18760

The present study was conducted to evaluate aspects of the reproductive tract of crossbred rams raised in the semi-arid region of the Brazilian Northeast. Correlations between measurements of the testes, epididymis and accessory sex glands and variables related to the spermatogenic process were also determined. Data were obtained from 19 animals slaughtered at the approximate age of 60 weeks. Seminiferous tubules were studied with regard to volume, length and height and the population of Sertoli and germ cells. Associations between variables were estimated by Pearson’s method (p < 0.05) and linear regression analysis using StatView 5.0 software (SAS, 1998). Significant correlations were found among all testis measurements (weight, length, width and volume) and other aspects of the reproductive trait, such as length of the cauda epididymis (CCauEp; r = 0.66 to 0.68) and weight of the accessory sex glands (AG; r = 0.68 to 0.72). Weight of AG was also associated with epididymal weight and CCauEp (r = 0.56 and 0.70, respectively), suggesting the existence of a synchronized development of the male reproductive trait. Testis width (TW) represented the variable with the most significant correlations with testis weight, length and volume (r = 0.88; 0.87 and 0.94). Moreover, regression model allowed the empirical estimate of testis volume (TV) based on testis width: TV = - 260.17 + 68.479 x TW (R² = 0.95). This characteristic (TW) was highly correlated with important aspects of gonad histology, such as volume of the seminiferous tubules (r = 0.96), number of round spermatids per testis (r = 0.89) and daily production of round spermatids (r = 0.89). Linear regression models with high coefficients of determination (R²) allowed the estimation of histological parameters based on testis width. In conclusion, the present study shows, for the first time, information about the weight of accessory sex glands in crossbred rams. It was also observed that animals with larger testes had larger epididymis and accessory sex glands and greater quantitative estimates of the spermatogenesis. Testis width should be useful for selection of sires because it is of easy measurement.