Diet Impacts for Mitigating Air Emissions from Poultry

Abstract

bstract. A series of experiments were conducted to evaluate emission reductions following implementation of diet strategies. Strategies included reduction of protein with supplementation of AA, diet acidification and dietary protein reduction. The impact of feeding these strategies on animal performance and emissions of NH3, H2S, NO, NO2, CO2, CH4, and non-methane total hydrocarbons (NMTHC) were compared to those of animals fed commercial diets (C). Groups of birds were housed in one of eight environmental chambers except turkeys that were housed in floor pens. Experiments lasted five weeks for hens, 16 weeks for turkeys, and 42 days for broilers. Emissions were calculated by sampling the incoming air followed by sequential sampling of each of the chambers for 15 min (10-min purge followed by a 5-min data recording period). Concentrations and airflow were measured every 30 sec and averaged for the 5-min period. When protein was decreased in broiler diets in part by feeding six feed phases vs. four in the control treatment, NH3 emissions decreased by greater than 40% over five flocks. Daily emissions of H2S, CH4, and NMTHC were not affected by treatment. In turkeys, formulation with three AA resulted in a 15% decrease in litter N. Feeding an acidifying diet coupled with decreases protein to hens, resulted in greater than a 35% decrease in NH3 emissions, and in a three-fold increase in H2S emissions due to inclusion of a sulfur containing acidulate. Our results demonstrate that diet modification can be a powerful tool for reducing emissions.