Body Temperature Regulation in Rabbits Exposed to Varying Ambient Temperatures in Plateau State

Thermoregulation is a fundamental physiological mechanism enabling homeothermic animals to maintain core body temperature within a narrow functional range despite environmental fluctuations. Rabbits are increasingly raised as a livestock species in Plateau State, North Central Nigeria, where the cool highland climate is generally considered suitable for rabbit production. However, temperature fluctuations between seasons present physiological challenges. This study investigated thermoregulatory responses in New Zealand White rabbits exposed to controlled ambient temperatures of 15, 22, 30, and 38 degrees Celsius in a climate-controlled chamber. Rectal temperature, ear pinna blood flow estimated by infrared thermography, respiratory rate, and heart rate were measured at each temperature after 60 minutes of exposure. At 38 degrees Celsius, rectal temperature rose significantly to a mean of 40.1 degrees Celsius, accompanied by markedly elevated respiratory rate of 210 breaths per minute and reduced postural activity. At 15 degrees Celsius, ear pinna temperature was significantly lower than at higher ambient temperatures, consistent with peripheral vasoconstriction to conserve heat. Heart rate was elevated at both thermal extremes. These findings indicate that rabbits maintained in Jos and surrounding areas require shade and ventilation management during warm season to prevent hyperthermia-related production losses. The study provides baseline thermoregulatory reference data for rabbit production in the Nigerian highland environment. Keywords: thermoregulation, rabbits, body temperature, Plateau State, heat stress.