Yearling scrotal circumference prediction equation and age adjustment factors for various breeds of beef bulls

Relationship between Scrotal Circumference, Quantitative Testicular Traits and Growth Performance in Tropically Adapted Yearling Beef Bulls Differing in Age

Scrotal circumference in yearling Hereford bulls: adjustment factors, heritabilities and genetic, environmental and phenotypic relationships with growth traits.

Field data on 4,233 yearling Hereford bulls were analyzed using fixed and mixed model least-squares procedures to examine factors affecting scrotal circumference; determine appropriate adjustment factors; and study genetic, environmental and phenotypic relationships among scrotal circumference and growth traits. Scrotal circumference was affected by postweaning feed level; contemporary group/fe...

Heritability Estimates and Adjustment Factors for Yearling Testicular Size in DifferentBreeds of Beef Bulls

A Comparison of Different Breeds for Growth Rates, Performance Traits and Scrotal Circumference in Young Beef Bulls

spring (a cow changing from a 6.0 to a 4.8) would be associated with an additional 15 days to first estrus after calving compared to a cow that maintained body condition. Similarly, a 20 percent decrease in body condition score would be associated with an additional 16 days to conception. This study reemphasized the relationship between weight loss during pregnancy and rebreeding performance. E...

Fertility of yearling beef bulls during mating.

Crossbred (Bos taurus) yearling beef bulls were assessed for breeding soundness and physical traits prior to multi-sire natural mating at pasture. Bulls (n = 60) were assigned to six groups of nine or 10 bulls and two bull-groups were rotated on 14-day intervals during a 63-day mating season in each breeding herd (n = 3) of 191-196 cows. The remaining bulls (n = 14) were maintained under simila...