Development of methodology and evaluation of sheep sweat gland characteristics from different genetic groups

Abstract

Under heat stress conditions, increases in respiratory frequency is the more important mechanism used by sheep to dissipate heat, especially in wool-on breeds. However, non-wool or semi-wool sheeps have more possibilities to exchange heat by skin, mainly by increasing the sweating rate. Thus, the objective of this study is to evaluate characteristics and types of sweat glands found in different genetic groups of sheep identifying those more adapted to heat stress conditions. During the summer of 2014 one skin sample of 10 animals purebred Santa Inês, Ile de France, Texel and Dorper and their crossbreds ½ Dorper + ½ Satnta Inês, ½ Texel + ½ Santa Inês and ½ Ilê de France + ½ Santa Inês will be collected at Embrapa and processed and analysed in the histology laboratory of the Faculdades Metropolitas Unidas - FMU. Type, size and quantity of the glands will be evaluated, according to a methodology adapted from Ribeiro et al. (2009) for cattle. This methodology will be used in other genetic groups in subsequent years of the project. (AU)