Heat stress in poultry production: Mitigation strategies to overcome the future challenges facing the global poultry industry.

Worldwide, the effect of climatic variations has become a great challenge in poultry production. As global climate is changing, it alters the environmental temperatures, precipitation patterns and atmospheric carbon dioxide. Poultry farming mainly depends on climatic conditions such as temperature and humidity. Several factors can be involved but heat stress is one of most important environmental factor influencing a wide range of chickens performances including reduced feed intake which, in turn, affects growth rate, body weight, meat quality, egg quality, egg production, semen quality and fertility; these negative influences result in great economic losses. Heat stress associated food safety issues have gained special importance due to public awareness and an abundance of available scientific information. Environmental modifications (early heat conditioning, open sheds and cooling systems) and nutritional strategies (early feed restriction, electrolyte, vitamin and mineral balance) cannot satisfy the special needs of stressed poultry. Therefore, there exists a crucial need to explore effective strategies including genetic markers to enhance thermo-tolerance and productivity of poultry birds in hot regions of the world.