Influence of water salinity on the adaptability of confined sheep in the Brazilian semiarid region

Résumé

The present study aimed to evaluate the thermal comfort indices inside the facilities and the influence of water salinity on the physiological responses of sheep in confinement receiving water with four levels of salinity (1.5, 3.0, 6.0 and 9.0 dS m^-1), consuming feed and water at will. The experimental configuration adopted was a completely randomized design (CRD), composed of 4 treatments and 6 replicates, with data submitted to analysis of variance (ANOVA) and means compared by Tukey test at 5% probability level. Air temperature, black globe temperature and humidity index and the thermal load of radiation at the hottest times of the day were above the thermal comfort zone for sheep, with low relative air humidity, factors that did not affect the rectal temperature, but caused elevation in surface temperature, respiratory rate and heart rate. Supplying water with salinity of up to 9.0 dS m^-1 did not affect (P>0.05) the physiological responses of sheep.