GM 04. Scrotal measurements, weight, and semen quality in Nellore bulls

Field data on 215 Nellore bulls (92sires and 123 sons), born from 1989 to 1993, were analyzed using DFREML methodology under uni and bivariate animal models to estimate heritabilities, phenotypic and genetic correlation between testis measurements, body weights and semen characteristics. Heritability estimates for scrotal circumference, left and right testis length and width were, respectively, 0.87, 0.89, 0.89, 0.90 and 8.85. Heritability estimates for motility, volume and vigor were, respectively, 0.12, 0.10 and 0.59. Genetic correlation between all testis measurements were high (from 0.61 to unit). Genetic correlation between scrotal circumference and semen motility, volume and vigor were, respectively, 1.00, 0.00 and 0.69