Effects of Multiple Litter Amendment Applications in Commercial Broiler Houses on Ammonia Emissions and Litter Microflora

Abstract

<abstract> Elevated ammonia (NH₃) concentrations in poultry operations can cause detrimental effects, such as respiratory disease outbreaks, slow growth rates, high mortality, and low feed efficiency. Acid-based litter amendments have been wildly used in broiler operations prior to bird placement to reduce NH₃ concentrations during the brooding period. Laboratory and small-scale field studies have shown that multiple litter amendment applications during grow-out could significantly reduce NH₃ emissions and improve production performance. A large-scale field verification study was conducted on a commercial broiler farm aimed at evaluating the effects of multiple sodium bisulfate applications during a six-week grow-out on air emissions and bacteria load in the litter of two identical broiler houses. Both houses received 488 g m^-2 of sodium bisulfate before chick placement in the brooding chamber. In one house, sodium bisulfate was applied at 244 g m^-2 (50 lb per 1000 ft²) on days 20 and 34, while the other house remained as the control. NH₃ concentrations and emissions were monitored throughout three flocks. Litter samples were collected three times per flock and evaluated for total aerobic bacteria, coliform bacteria, and yeast and mold counts using Petrifilm. Immunoassays were used to test for the presence or absence of and in litter enrichment cultures. Multiple litter amendment applications significantly reduced NH₃ emissions by 25.8% over the grow-out (p < 0.01). No significant difference was observed between treated and untreated poultry litter with respect to microbial counts. was not detected in the treated house over the three flocks but was found in the control house. was not influenced by multiple amendment applications.