The hair follicle and apocrine gland populations of Zebu (Bos indicus L.) and Shorthorn (B. taurus L.) cattle skin.

Abstract

Skin samples taken with a trephine of known size from Shorthorn (Bos taurus L.) and Zebu (B. indicus L.) cattle were used to determine the density of hair follicles and apocrine glands in the skin. The repeatability of the measurement of density on the same animal was found to lie between 78 and 90 per cent. The expansion of the skin as the animal grows, and the manner in which the plane of nutrition can modify growth and so the extent of expansion, has a predominating effect on the hair follicle and apocrine gland density. There is a significant difference between ages, but for each breed the regression coefficients of log follicle number on log heart girth within age groups are not significantly different. The mean number of hair follicles per sq. cm in Zebus was 1698, in Zebu crosses 1321, and in Shorthorns on a low plane of nutrition 1064. In Shorthorns on a high plane the number was 764. All differences were statistically significant.