Study on deodorizing and carbon reducing effect of different meal protein raw materials in fattening pigs under simulated fermentation in vitro

With the increasing public concern and demand for air quality, the development of animal husbandry has been limited due to the problem of odor emissions.In this study, intestinal microecological fermentation model was simulated in vitro.Four feed materials, including soybean meal, rapeseed meal, cottonseed meal and corn germ meal, were fermented by fresh pig manure from 120 days old Duroc Landrace Yorkshire hybrid finishing pigs.To investigate the difference of nutrient composition, odor yield and fecal flora structure of different fermented feed materials.The results showed that the Branched-chain amino acids(BCAAs) content of the three kinds of corn germ meal was more balanced, the Total Gas, CO2 and NH3 gas production content of soybean meal K was the highest, the H2S gas production of cottonseed meal H was the highest, and the gas production of rapeseed meal J, corn germ meal H, Q was relatively low.The results of 16S rRNA gene sequencing showed that Bacillus, unclassified_c_Bacilli and unclassified_f_Lachnospiraceae in the microbial community could reduce CO2 and H2 gas production. Megasphaera may promote the production of H2S and H2.Increasing the use ratio of rapeseed meal J, corn germ meal H, Q in feed to replace soybean meal can better achieve the effect of source deodorization, and provide a basis for the green and low-carbon development of animal husbandry.