Evaluation of the efficacy of amendment types and rates in reducing ammonia emissions from broiler litter.

Several amendments have been used to reduce ammonia (NH) emissions from broiler litter (BL); however, a comparative study between amendments and their application rates has not been fully explored. This study evaluated the potential of biochar (B), zeolite (Z), Flue Gas Desulphurization-Gypsum (FGD-G), and sodium bisulfate (S) at four application rates in reducing NH emissions from BL. The treatments comprised of amendment types (4) and their application rates (4), and a control with no amendment for a total of 17 treatments replicated twice and arranged in a completely randomized design. The treatments were incubated at 30 °C for 40 days at a moisture content of 40% (w/w), and NH emissions were measured every day for the first 10 days and 3 days intervals afterward for 40 days. Results showed that the application of 13 and 17% B (w/w) reduced cumulative NH emissions by 41 and 46%, respectively, compared to control over a 40-day period. Zeolite application at 8 and 11% reduced NH by 20 and 33%, respectively. There was no significant difference between the different rates of FGD-G, and they were generally less effective; however, a 15% FGD-G rate reduced NH by 9.1%. Application of S at rates of 2, 4, 6, and 7% significantly reduced NH emissions by 91, 99, 100, and 100 %, respectively. The effectiveness of amendments to reduce ammonia emissions followed the order: S > B > Z > FGD-G. These findings contribute to an ongoing effort to identify non-acidic amendments to minimize NH emissions in broiler houses.