Coat characteristics and physiological responses of locally adapted ewes in semiarid region of Brazil

Wirton Peixoto Costa, Edgard Cavalcanti Pimenta Filho, Jacinara Hody Gurgel Morais Leite, Wallace Sóstene Tavares da Silva, Wilma Emanuela da Siva, Francisco Helton Sá de Lima, Gilvan Nogueira Alves Peixoto-Júnior, Débora Andréa Evangelista Façanha

Abstract


This study aimed to evaluate the effects of heat stress and characterize the coat characteristics of red and white varieties of Morada Nova sheep raised in the semiarid region of Brazil during the rainy and dry seasons. The following variables were investigated: coat thickness (CT), inclination angle of the coat (?I), hair coat density (HDE), hair length (HL) and hair diameter (HD), in conjunction with the physiological responses of rectal temperature (RT) and respiratory rate (RR). The data were tested with an analysis of variance, a Tukey test at a 5% significance level and a correlation analysis. The season of the year (dry and rainy) and the variety (red and white) were used as fixed effects in the analysis of variance. HL, HDE and HD were significantly greater in the dry season than in the rainy season (P < 0.05), but CT and ?I did not differ between seasons (P > 0.05). HL, HDE and HD were lower and ?I was greater (P < 0.05) for the red variety, but CT was statistically equal (P > 0.05) for the two varieties. It was concluded that the coat characteristics of the Morada Nova ewes favor the adaptation of the sheep to a semiarid environment, including the improved protection of the skin against ultraviolet radiation. In general, the white variety presented characteristics reflecting a higher degree of adaptation to the conditions of the Brazilian semiarid region.

Keywords


Conservation of animal genetic resources; Hair coat; Sheep; Tropical environment.

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DOI: http://dx.doi.org/10.5433/1679-0359.2018v39n3p1281

Semina: Ciênc. Agrár.
Londrina - PR
E-ISSN 1679-0359
DOI: 10.5433 / 1679-0359
E-mail:  semina.agrarias@uel.br
Este obra está licenciado com uma Licença  Creative Commons Atribuição-NãoComercial 4.0 Internacional