~ 237 ~ The Pharma Innovation Journal 2017; 6(9): 237-245 ISSN (E): 2277- 7695 ISSN (P): 2349-8242 NAAS Rating 2017: 5.03 TPI 2017; 6(9): 237-245 © 2017 TPI www.thepharmajournal.com Received: 07-07-2017 Accepted: 08-08-2017 Tushar Jyotiranjan Department of Veterinary Physiology, C.V.Sc & A.H. Orissa University of Agriculture and Technology, Bhubaneswar- 03, Odisha, India Swagat Mohapatra Department of Veterinary Physiology, C.V.Sc & A.H. Orissa University of Agriculture and Technology, Bhubaneswar- 03, Odisha, India Chinmoy Mishra Department of Animal Breeding and Genetics, C.V.Sc & A.H. Orissa University of Agriculture and Technology, Bhubaneswar- 03, Odisha, India Nirupama Dalai Department of Veterinary Physiology, C.V.Sc & A.H. Orissa University of Agriculture and Technology, Bhubaneswar- 03, Odisha, India Akshya Kumar Kundu Department of Veterinary Physiology, C.V.Sc & A.H. Orissa University of Agriculture and Technology, Bhubaneswar- 03, Odisha, India Correspondence Chinmoy Mishra Department of Animal Breeding and Genetics, C.V.Sc & A.H. Orissa University of Agriculture and Technology, Bhubaneswar- 03, Odisha, India Heat tolerance in goat- A genetic update Tushar Jyotiranjan, Swagat Mohapatra, Chinmoy Mishra, Nirupama Dalai and Akshya Kumar Kundu Abstract Livestock undergo various kinds of stress such as physical, nutritional, chemical, psychological and thermal stress. Among them thermal stress is most concerning now a days in the ever changing climatic scenario. High ambient temperatures, high direct and indirect solar radiations, and humidity are environmental stressing factors, according to the climatic changes. Thermal stress redistributes the body resources including protein and energy at the cost of decreased growth, reproduction, production and health. Goats (Capra hircus) are relatively resistant to harsh environmental conditions. Thermal stress stimulates sort of complex responses which are fundamentals in the preservation of cell survival. Physiological responses to thermal stress are change in rectal temperature, respiration rate, heart rate and skin temperature. Heat tolerance in goat is controlled by heat tolerance genes such as HSP32, HSP40, HSP60, HSP70, HSP90, HSP90AB1, HSP110, CRP, VEGF, cNOS, iNOS etc. At molecular level changes in gene expression of proteins ensure protections. Altogether these physiological, biochemical and molecular responses make the goats to survive in harsh environment. Keywords: Gene, Goat, Stress, Temperature, Response Introduction Due to climatic variations and global warming, threats are become major to affect the sustainability of livestock production system. Climate change poses formidable challenge to the development of the livestock sector [1] . International panel for climate change (IPCC) indicated an increase in temperature by 0.2 0 C per decade and predicted that the surface temperature of the earth may increase between 1.8 0 C to 4 0 C by the end of this century [2] . Stress has been conceived as a reflex reaction that occurs ineluctably when animals are exposed to adverse environmental conditions and which is the cause behind many unfavorable consequences, ranging from discomfort to death of the animal [3] . The rise in temperature along with increased precipitation resulting from climate change is likely to aggravate the heat stress in animals affecting their productive and reproductive performance [4,5] . Ruminants do not maintain strict homeothermy under stress despite having well developed mechanism of thermoregulation. The environmental stressing factors that improve strain on animals are high ambient temperature, solar radiation and humidity [6] . High environmental temperature challenges animals’ ability to maintain energy, thermal, water, hormonal and mineral balance [7] . Stress is reaction of the body to stimuli that disturb homeostasis often with detrimental effects. Among all the stress factors, thermal stress is most concerning now a days in the ever changing climatic scenario. In tropical and sub tropical regions, high ambient temperature is the major constraint on animal production, whereas extreme low temperature in temperate regions is also detrimental to livestock. Thermal stress includes both heat stress, during extreme summer season as well as cold stress, during extreme winter season. High environmental temperature is the major concern in tropical and arid areas whereas at the same time very low environmental temperature in temperate areas is also lethal. Temperature determines metabolic rates, heart rates and other important factors within the bodies of animals, so an extreme temperature change can easily distress the animal body. The effect of high temperature is further aggravated when heat stress is accompanied by high ambient humidity. Since 9000 BC, goat is the oldest domesticated species of the Indian subcontinent [8] . Globally goat plays an important role in the economy of thousands poor livestock owners who earn their livelihood by rearing them in different terrain and climatic conditions. Goat rearing is a traditional occupation of small, marginal farmers and landless laborers in semiarid, arid and