ADJUSTMENT FACTORS OF SCROTAL CIRCUMFERENCE FOR YEARLING AGE AND WEIGHT EFFECTS IN NELORE CATTLE.

L. T. DIAS, R. A. TEIXEIRA, L. EL FARO, L. G. ALBUQUERQUE

Abstract


Data of scrotal circumference (PE) of 9,355 Nelore bulls from 382 contemporary groups (GC) were analyzed to estimate the adjustment factors to be used in genetic selection programs. Contemporary group was defined by year and season at birth, farm and management group at birth, weaning and yearling. The means and standard deviations of scrotal circumference (PE), yearling age (IDS) and yearling weight adjusted to 550 days (PSAJ) were respectively: 26.33 ± 3.18 cm, 545.09 ± 41.19 days, and 319.71 ± 35.76 kg.
KEY-WORDS: Adjustment factor. Beef cattle. Precocity. Scrotal circunference. Sexual precocity.



DOI: http://dx.doi.org/10.15361/2175-0106.2005v21n1p96-100