Adaptive parameters and thermal comfort of postpartum ewes fed on concentrate supplementation in grazing system/Parametros adaptativos e conforto termico de ovelhas deslanadas no pos-parto submetidas a suplementacao concentrada em sistema de pastejo

Current analysis evaluated adaptive parameters and thermal comfort of postpartum ewes fed on concentrate supplementation in grazing system. Thirty lactating pluriparous sheep, 16 Santa Ines (SI) and 14 Morada Nova (MN) were used. Physiological parameters such as respiratory rate (RR), heart rate (HR) and rectal temperature (RT) were measured, in that order, with the animals at rest in the morning (6:00-7:00 am) and in the afternoon (1:00-2:00 pm), respectively, every seven days, with 10 samples. A significant effect (p < 0.05) for RR and HR was reported in the strain. Similar behavior was reported for RR between the breeds where MN sheep had high adaptability. Supplementation levels of 0.5 and 1.5% influenced (p < 0.05) RR which was stronger in the sheep that received the highest supplementation level, possibly due to calorie increase in the diet. However, HR and RT parameters did not differ within the breed due to supplementation. HR was higher between the breeds for SI sheep at 0.5%. Results show that concentrated supplementation affected the respiratory rate of ewes in the postpartum period, with higher calorie increment at 1.5% level and superiority for Santa Ines ewes. Greater adaptability of Morada Nova sheep has been indicated when fed on concentrated diet in grazing system. Keywords: environmental factors, heat stress, nutrition, thermoregulation. Objetivou-se avaliar os parametros adaptativos e o conforto termico de ovelhas deslanadas no posparto submetidas a suplementacao concentrada em sistema de pastejo. Foram utilizadas 30 ovelhas pluriparas em lactacao, sendo 16 da raca Santa Ines e 14 da raca Morada Nova. Os parametros fisiologicos, frequencia cardiaca (FC), frequencia respiratoria (FR) e temperatura retal (TR) foram aferidos nessa ordem com os animais em repouso nos periodos da manha e da tarde, de 6:00-7:00 e 13:00-14:00, respectivamente, a cada sete dias, totalizando dez coletas. Houve efeito de turno (p < 0,05) para FR e FC dentro de raca. Comportamento semelhante foi observado para FR entre racas, em que as ovelhas Morada Nova apresentaram maior adaptabilidade. Os niveis de suplementacao de 0,5 e 1,5% exerceram influencia (p < 0,05) sobre a FR com superioridade para as ovelhas que receberam maior nivel de suplementacao, possivelmente pelo incremento calorico na dieta. No entanto, os parametros FC e TR nao diferiram dentro de raca em funcao da suplementacao, sendo que entre racas a FC foi superior para ovelhas SI a 0,5%. Conclui-se que a