Ameliorative measures to counter heat stress in poultry

Heat stress is one of the main challenges in poultry production as it reduces performance in broilers and layers. This review focuses on the impact of heat stress in poultry production with emphasis on broilers and layers, methodologies to measure the severity of stress and dealing the preventive measures to alleviate stress due to heat. Potential use of naked neck and frizzle genes is highlighted. Nutritional interventions including offering a balanced diet, increasing energy, required amino acids, vitamins like vitamins A, E, Se and minerals like Ca, Na, Cl and K additional supplementation of vitamin C, provision of cool water at levels of up to five times of feed intake to satisfy the special needs during heat stress all have proven advantages. Designing housing with gable type roofing and open sided, wet curtains/exhaust fans, tunnel ventilation in environment control houses, provision of more floor space and free movement, to exhibit natural movement and decreasing flock density is useful to minimise stress as well as to regulate the temperature in micro environment. Thermos tolerance in birds can be enhanced by early feed restriction, good management with better ventilation and developing of heat tolerant breeds by selecting for less feathers. Selection of breeds suitable to climate, nutritional manipulation and small management changes can minimise heat stress in birds.