VARIATIONS IN THE THERMOREGULATORY RESPONSE OF GEESE DURING LOW TEMPERATURE – HUMIDITY INDEX

Abstract

In a 28–day trial, the effects of sex and daytime on the thermoregulatory response of geese during low temperature – humidity index was investigated. Twenty four geese (12 males and 12 females) were allotted into two treatments according to their sex in a completely randomized design. Their cloaca temperature, respiratory rate and pulse rate were measured and recorded in the morning, afternoon and evening for the entire experimental period. Also, the ambient temperature and relative humidity of the pen were recorded daily. Males had significantly (p < 0.05) higher respiratory rate (20.84±2.06 breaths/minute) than females (19.49±1.37 breaths/minute). However, pulse rate and cloaca temperature were not significantly (p > 0.05) different between the two sexes. The respective mean temperature, humidity and temperature-humidity index (THI) values recorded were 25.20±1.460C, 91.93±4.38% and 24.92±1.38 (morning); 28.98±1.870C, 73.64±9.00% and 27.74±1.37 (afternoon) and 28.88±2.300C, 72.39±8.87% and 27.60±1.86 (evening). The cloaca temperature in the morning was significantly (p < 0.05) lower than in the afternoon and evening while their pulse rate and respiratory rate were not significantly (p<0.05) different at the respective daytimes. Hence, sex and daytime independently influenced the thermoregulatory response of the geese.