Effect of altered microclimate on alleviating heat stress in sheep

The present research was conducted to study the effect of fan and foggers on Temperature Humidity Index (THI) and physiological responses in Nellore brown sheep during summer. Twenty ewes of age 3-5 years from sheep unit of Livestock Farm Complex of NTR college of Veterinary Sciences, Gannavaram were divided into 2 groups of each 10 ewes each in a completely randomized design on the basis of body weight. The animals in the group-I were considered as control whereas the animals in the group-II were equipped with fan and foggers for modification of microclimate in the shed. Data on temperature-humidity index and various physiological responses were recorded and analysed statistically. Analysis revealed that, the day average THI was significantly higher in control group (85.67±0.40) as compared to treatment group (83.45±0.30). No significant difference was observed in the morning THI whereas in evening THI significant difference was observed between control (86.84±0.51) and treatment group (83.35±0.36). The average rectal temperature, average respiration rate and average pulse rate was significantly lower in treatment group (102.41±0.04, 41.61±0.81, 87.94±0.52) as compared to control group (103.02±0.05, 57.91±1.29, 95.42±0.55). No significant difference was observed in the morning recorded physiological responses. Therefore, it can be concluded that microclimate modification with the help of foggers and fans is a means to protect the animals from thermal stress under intensive sheep production system during the summer season.