Ammonia levels during broiler rearing cycle

The evaluated ammonia volatilization rates and its association with humidity, temperature, and pH in broiler litter in conventional and dark house rearing systems. Evaluations were performed at 0.01, 1.00, and 1.50 m high, using a completely randomized design, at a weekly frequency for 12 weeks­from the sanitary void to the end of the 42-day cycle. Litter temperature had no significant difference for different types of house. Humidity and pH levels varied according to houses and evaluation periods. No ammonia volatilization was detected during initial periods. However, up from the 21st day of rearing, rates started to increase, showing higher concentrations at 0.01 m height. At 1.00 and 1.50 m, values around 20 mL·m­3, were obtained and considered an acceptable exposure level for the broilers and employees directly working in this sector. Yet, broiler breeders should target lower levels due to environmental impacts.