Variáveis fisiológicas e estruturas do tegumento de ovinos e caprinos criados no semiárido brasileiro.

Abstract

The objective of this study was to evaluate the effect of two seasons of the year on the adaptability of goats and sheep raised in an extensive system in the Paraíba semi-arid region, through physiological parameters, adaptability tests, structural characteristics of the pelage, sweating rate and integument structures. Two consecutive experiments were performed. In the first experiment 24 animals were used, 12 Santa Inês sheep and 12 Moxotó goats. Evaluated eight times during the months of July to October 2016. Rectal temperature (TR), respiratory rate (FR) and surface temperature (TS), the heat tolerance index (ITC) and the heat tolerance coefficient (CTC). The ITC has revealed that the animals are adapted to the climatic conditions. Females CTC showed higher (P <0.05) than males. In general, there was no significant difference between goat and sheep species for rectal temperature and respiratory rate. The analysis of variance revealed significant interaction (P <0.05) of the species and within the seasons, on TS. In the second experiment, a completely randomized design was used in a factorial scheme of 2x2 (2 species, 2 sexes) 2x2 (2 species and 2 sexes) with 5 replicates. Twenty animals, 10 Santa Inês sheep and 10 Moxotó goats were used. The animals were kept in an extensive system, evaluated only once during the month of November, during the hot season of 2016. The characteristics evaluated were: cape layer thickness (ECP), number (NP), length (CP) and weight (PS) of the hairs, the numerical (DN) and volumetric (DV) density. The capacity of the sweating rate (TS) of the animals, as well as structures of the integument such as: hair follicle, sweat glands (GSu) and epidermis thickness (EEp). The sex of the animals did not influence (P> 0.05) in any of the evaluated variables. (P <0.05) than sheep, but PS and BV of sheep were higher (P <0.05). The sheep had a higher GSu number and a higher EPS (P <0.05) than the goats. TS had no statistical differences (P> 0.05). Both species have been shown to be physiologically well adapted and with the characteristics of the fur and sturgeons of the tegument favorable to the climatic conditions of the Semi - arid.