Introduction
Climate change is one of the biggest daunting challenges faced globally, with severe and widespread deleterious effects, warming the planet, threatening ecological systems and disrupting the life cycle of several species.
Global climate change is mostly caused by greenhouse gas (GHG) emissions that result in warming of the atmosphere. The changing environment jeopardizes the achievement of human development and poses as a major threat to the poor who rely heavily on the natural resource base for their livelihoods. The world average temperature was projected to rise in the range of 0.3-4.8 °C by 2100. Even 1 °C raise in temperature can hamper the delicate balance of ecosystems and affect plants and animals that inhabit them. Therefore, this urges the need to warrant implementation of immediate actions to build the resilience of agricultural production systems.Poultry industry is in leading position among the agricultural and allied sectors. Poultry meat and eggs are the good source protein which is beneficial for millions of people in below poverty. The consumption of poultry meat and eggs has advantageous over other livestock products since there is no religious taboos and affordable to everyone including economically poor peoples. Poultry meat contains less saturated fats and more micronutrients. Heat or cold stress has arisen as one of the major constraints for poultry production system particularly in the hot and humid tropical and temperate regions. Absence of sweat glands makes thermoregulation becomes challenging for the birds during hot weather, thus compromises their production potential. Moreover, chronic heat stress causes bird mortality. Therefore, this chapter elaborate in detail about the negative impacts of heat or cold stress on poultry production and thermoregulatory responses in birds.
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