Physiological responses, ethology, and ingestive behavior of Anglo-Nubiana goats submitted to different air temperatures

The objective of this study was to evaluate the physiological parameters and ingestive behavior of Anglo-Nubian goats as a function of air temperature, as well as the correlation of these variables. Six male goats were distributed in a completely randomized design in a climate chamber. The treatments consisted of four different controlled AT (20, 24, 28 and 32 °C). The physiological responses: heart rate (HR), respiratory rate (RR) and rectal temperature (RT) were collected at three different times of the day (8 am, 12 pm and 4 pm). The behavioral responses evaluated were: lying inactive, standing inactive, feeding, standing ruminating and lying ruminating. The feed intake decreased linearly in the hours of 4–7 AM, according to the increase in AT. The time spent in the lying ruminating activity decreased linearly (P<0.05) with the increase in AT. The intake and the rate of dry matter intake decreased linearly (P<0.05) with the increase in AT and the water intake increased linearly (P<0.05). The overall results provide information that can be used in heat tolerance studies, helping livestock farmers around the world to plan and make decisions. In addition to contributing to the development of strategies, national and international guidelines for mitigation and accurate assessment of thermal stress.