Data/hora: 05/06/2024 14:00:23

Biblioteca(s): 	Embrapa Suínos e Aves.	
Data corrente: 	04/11/2020	
Data da última atualização: 	05/11/2020	
Autoria: 	BAENA, M. M.; COSTA, A. C.; VIEIRA, G. R.; ROCHA, R. de F. B.; RIBEIRO, A. R. B.; IBELLI, A. M. G.; MEIRELLES, S. L. C.	
Afiliação: 	MARIELLE MOURA BAENA, UFL; ADRIANO CARVALHO COSTA, UFG; GABRIELA RODRIGUES VIEIRA, UFL; RENATA DE FÁTIMA BRETANHA ROCHA, UFL; ANDREA ROBERTO BUENO RIBEIRO, FMU; ADRIANA MERCIA GUARATINI IBELLI, CNPSA; SARAH LAGUNA CONCEIÇÃO MEIRELLES, UFL.	
Título: 	Heat tolerance responses in a Bos Taurus cattle herd raised in a Brazilian climate.	
Ano de publicação: 	2019	
Fonte/Imprenta: 	Journal of Thermal Biology, v. 81, p. 162-169, 2019.	
DOI: 	https://doi.org/10.1016/j.jtherbio.2019.02.017	
Idioma: 	Inglês	
Conteúdo: 	Abstract: Knowledge of thermoregulatory responses in taurine cattle contribute to identification of animals most adapted to heat and productive when raised under Brazilian climate. The objectives were to verify the morphological and physiological responses related to adaptation to heat of taurine breeds raised under in Brazilian meteorological conditions in different seasons of the year and day periods, and to detect differences within and between breeds to know breed is most adapted. Measurements were made of 74 young bulls (n=31 Angus; n=43 Simmental) for the morphological traits: hair length (HL), number of hairs (NH), and coat thickness (CT); and for the physiological traits: respiratory rate (RR) and hair coat surface temperature (ST). The temperature-humidity index (THI) was calculated. The data were subjected to analyses of variance, cluster analysis, and principal component analysis (PCA). The THI (< 74) indicates thermal comfort. In the winter, the HL and CT higher than in the spring season (P < 0.0001) in both breeds. Angus exhibited higher HL and CT (P < 0.0001). Within each breed, the animals differed from one another for HL (P < 0.0005). In the spring, CT was similar between the breeds, differing only in the winter season. Angus had higher values (P < 0.0005) of RR and lower values (P < 0.0001) of ST. Both breeds had higher (P < 0.0001) RR and ST in the afternoon. PCA showed that NH and HL better explained variation in adaptation. In general, the breeds have similar morphological responses in the hottest months, but have different physiological responses; Simmental proves to be more physiologically resistant. The afternoon was more stressful than the morning, even though the animals were in a thermal comfort zone. Measuring traits related to hair coat is sufficient for effective evaluation of adaptation, and the season affects the morphological and physiological traits of taurine cattle raised.	
Palavras-Chave: 	Adaptabilidade; Adaptability; Qualidade da carcaça; Taurine cattle; Tropical weather.	
Thesagro: 	Bos Taurus; Clima Tropical; Genética Animal; Pecuária; Produção Animal; Termorregulação.	
Thesaurus Nal: 	Brazil; Carcass quality; Cattle production; Livestock; Thermoregulation.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Suínos e Aves (CNPSA)	
Exemplares: 	CNPSA - (21961-1) - UPA - AP - DD -  -  -  - DIS