Journal of Animal Environmental Science ISSN:1226-0274(Print) 축산시설환경학회지

This study was investigated characteristics and components of odor reducing agents used in livestock farms, and evaluate the efficacy of reducing odors in pig manure through in vitro fermentation. As a result of classification according to major components, microbial agents (71.3%), amino acid supplements (11.7%), composite type (6.1%), silicate supplements (4.9%), extract (2.8%), vitamin supplements (2.0%), and enzyme (1.0%) were investigated. The microbial agents (n=176) showed that Bacillus subtilis accounted for the highest percentage (10⁶~10¹¹ CFU/g). When the biological agents were evaluated an odor reduction efficacy, ammonia was reduced by 6.06, 29.38 and 15.49% of the control group in Treatment I (plant extracts), Treatment II (Bacillus subtilis-based complexes) and Treatment III (yeast and lactic acid bacteria complexes), respectively. When bacterial changes were observed during in vitro fermentation, total bacteria was increased 1.22∼4.02 × 10⁹ CFU/g at the beginning of culture to 2.51 × 10⁹~1.03 × 10¹⁰ CFU/g at the end of culture. Bacillus subtilis showed higher levels in Treatment I and Treatment II than the additive-free group and Treatment III. Lactobacillus sp. maintained higher levels in the additive group than the non-additive group. Yeast was not detected at the end of the culture. Livestock farms are using various odor reducing agents, and their effects vary depending on the characteristics of the products. Therefore, the understanding about odor generation in farms and characteristics of odor reducing agents should be prioritized for effective odor control.