Effect Of Hot Environment On Physiological Responses Of Rabbits

This study was carried out at the experimental rabbit farm of Animal Production Department, Faculty of Agriculture, Zagazig University, Zagazig, Egypt. The first experiment aimed to study the development of thermoregulatory system at different ages of newborn rabbit beginning one day of birth to 20 days. In addition, the second one was undertaken to study the effect of different temperature on physiological traits and determination of thermoneutral zone of Giza white rabbits and New Zealand rabbits at weaning.The results could be summarized as follows:For the first experiment, the best age for giving survival time (min.) as well as mortality rate (%) was newborn rabbits aged 15 days, This means that the functional development of thermoregulatory system in rabbits start to be well developed at 15 days after birth.For second experiment, exposure Giza and New Zealand White rabbit to high temperatures 30, 32.5 and 35°C significantly affected some physiological studied traits i.e., ear temperature, fur temperature and skin temperature. On the other hand, rectal temperature and respiration rates were significantly increased after exposure of rabbit used breed to 32.5°C and 35°C. Comfort zone was 22-25°C in New Zealand White rabbits. While, it was 20-25°C in Giza white rabbits, this explain that the comfort zone was longer in Giza white rabbits than in New Zealand White rabbits, thus, Giza white rabbits has higher adaptability than New Zealand White rabbit under Egyptian conditions.