Summer and heat stress

16-07-2009 | |

Summer has arrived in many parts of the world and heat stress is again the center of attention. Decreased feed intake, lower than expected body weight gain, poor feed efficiency, reduction in egg production/eggshell quality/hatchability, and increased daily mortality are adverse effects of heat stress often seen in broiler and layer poultry flocks.

The magnitude of problems resulting from heat stress may vary from region to region, and also from one farm to another (in the same region). These effects may not be the same in different barns of a farm. There is no doubt that temperature itself is a determining factor, but farm structure (e.g. barn design, ventilation system, stocking density, litter condition) and the way that farm staff handle heat stress are also important factors that will also influence the outcome of this problem. Birds, depending on type and stage of production, react differently to heat stress conditions.

Strategies such as changing the lighting programme, temporary feed restriction, or feeding at specific times of the day, increasing density of nutrients in diet as feed intake decreases during heat stress, providing birds with extra electrolytes and vitamins (especially through drinking water) may be of some help (1). It is always recommended to provide birds with cool water during high temperatures, but I am not sure how this can happen when the temperature is something around 45-50 ºC.

How do you deal with heat stress in your farm?