Resumen de GM 20. Evidence for the existence of a major gene influencing hair Length and heat tolerance in bos taurus cattle
T. A. Olson, A. C. Hammond, C. C. Chase
A total of 28 calves from Angus sires and Senepol × Hereford or Hereford × Senepol dams were evaluated for hair length, rectal temperatures, respiration rates, and weights. In addition, ten purebred Angus calves were included in the study as control. Measurements were taken on three consecutive weeks during the hot summer months and also during the cooler late fall. Length of the hair was evaluated using a subjective system of classification (1 - 4). The lowest values describe the typical extremely short hair of pure Senepol cattle and of its crossings F1 with Bos taurus. Twelve of the 28 calves were thus coded as slick-haired and 16 as normal-haired; this ratio does not differ significantly from the 1:1 ratio. Rectal temperature (RT) of the yearling calves of short hair was smaller (P
