Data/hora: 19/06/2024 15:13:05

Biblioteca(s): | Embrapa Caprinos e Ovinos; Embrapa Pecuária Sudeste.
Data corrente: | 26/04/2023
Data da última atualização: | 26/04/2023
Autoria: | RODRIGUES, J. N. D.; GUIMARÃES, J. D.; FONSECA, J. F. da; PENITENTE-FILHO, J. M.; RANGEL, P. S. C.; RAMÍREZ LÓPEZ, C. J.; FREITAS, R. S.; CASTILHO, E. F. de; RODRIGUES, L. F. de S.; OLIVEIRA, M. E. F.; GARCIA, A. R.
Afiliação: | JULIANA NASCIMENTO DUARTE RODRIGUES, Universidade Federal de Viçosa; JOSÉ DOMINGOS GUIMARÃES, Universidade Federal de Viçosa; JEFERSON FERREIRA DA FONSECA, CNPC; JURANDY MAURO PENITENTE-FILHO, Universidade Federal de Viçosa; PAULO SERGIO CERQUEIRA RANGEL, Universidade Federal de Viçosa; CAMILO JOSÉ RAMÍREZ LÓPEZ, Universidade Federal de Viçosa; RAFAEL SOUZA FREITAS, Universidade Federal Rural da Amazônia; ERICK FONSECA DE CASTILHO, Universidade Federal Rural da Amazônia; LUIZ FERNANDO DE SOUZA RODRIGUES, Universidade Federal Rural da Amazônia; MARIA EMILIA FRANCO OLIVEIRA, Universidade de São Paulo; ALEXANDRE ROSSETTO GARCIA, CPPSE.
Título: | Climatic seasons and time of the day influence thermoregulation and testicular hemodynamics in Santa Inês rams raised under humid tropical conditions.
Ano de publicação: | 2023
Fonte/Imprenta: | Journal of Thermal Biology, v. 114, article 103546, May, 2023.
DOI: | https://doi.org/10.1016/j.jtherbio.2023.103546
Idioma: | Inglês
Conteúdo: | Abstract: This study evaluated the possible association between the diurnal variations of climatic factors during the rainy (RS) or less rainy (LS) seasons on the testicular hemodynamics and thermoregulatory responses of hair sheep rams raised in a humid tropical climate. Santa Inês rams (n = 6) underwent evaluation of general and testicular physiological parameters (heart and respiratory rates, internal and scrotal temperatures, internal-scrotal temperature gradient, scrotal distention, and color Doppler ultrasound evaluation of the spermatic cords and spectral analyses of testicular arteries) over six consecutive weeks per season at three separate times daily (morning = 8:00 a.m., noon = 12:00 p.m., and afternoon = 5:00 p.m.) during the RS and LS. Climatic air temperature and relative humidity data were recorded, and the temperature and humidity index (THI) was calculated. Higher thermal challenge was observed in LS relative to RS (air temperature = 28.0 vs. 30.9 °C; relative humidity = 84.1 vs. 69.9%; THI = 80.0 vs. 82.5; P < 0.05). In both seasons, respiratory rate and internal temperature were normal, demonstrating the animals? adaptability. In RS, however, a higher scrotal temperature was recorded in relation to LS (35.0 vs. 34.7 °C; P < 0.05), with a gradual increase from morning to afternoon. Lower resistivity (0.40 vs. 0.64; P < 0.05) and pulsatility (0.55 vs. 1.14; P < 0.05) indices, and a higher rate of high-velocity blood flow of testicular arteries (71.1 vs. 60.6%; P < 0.05) were observed in RS compared to LS. The lowest correlations between testicular hemodynamic, physiological variables, and environmental parameters (P < 0.05) were observed in the morning. In conclusion, testicular thermoregulation and testicular hemodynamics were influenced by the climatic seasons and time of the day, being more efficient in the LS season and with less interference from environmental factors in the morning.
Palavras-Chave: | Cordão espermático; Doppler ultrasound; Haemodynamics; Hair sheep; ILPF; Physiological parameters; Testicular hemodynamic; Tropical climate.
Thesagro: | Ovino; Ultrassom.
Thesaurus Nal: | Brazil; Climatic factors; Environmental factors; Spermatic cord; Thermoregulation.
Categoria do assunto: | L Ciência Animal e Produtos de Origem Animal
Registro original: | Embrapa Caprinos e Ovinos (CNPC)

Exemplares:

CNPC - (40547-1) - UPC - AP - DD -  -  -  - DIS
CPPSE - (25983-1) - UPC - AP - DD - PROCI-2023.00027 - ROD - 2023.00080 - DIS