The Selection of Volatile Fatty Acid Reduction Microbe Bacillus thuringiensis D45 and its VFA Reduction Effect
Takeshi ONOUE, Tomoko SHIMOKAWA, Yoshitomo KUSAKA, Minoru MAEDA, Hiroyuki SAITOU and Kenichi ASADA
The VFA emission in a pig house influences sense of smell with a very small amount. The VFA re- duction in a pig house is important for the malodor measures of the piggery. In this study the selection of the microbe that has ability for superior VFA reduction was considered from 515 Bacillus libraries, and its VFA reduction microbe which mixed with feed was given to a pig. Microbes that were inoculated into VFA addition nutrient medium, were judged by ability for increase, and some microbes were se- lected at first. As for the primary selection microbes, were measured VFA reduction ability. The microbe Bacillus thuringiensis D45 indicating the most excellent VFA reduction was selected at last. The D45 that was inoculated into pig feces suspension, and cultured under an aerobic condition, reduced VFA. The D45 does not influence health and dissection views and does not infiltrate the internal organs even if it was given to a piglet. The D45 was not detected in rectal feces 1 week later of the mixture stop. The D45 given to a growing-finishing pig reduced VFA without having an influence on feeding and the DG. The D45 that was mixed 105 CFU/g with feed，and was given to a growing-finishing pig reduced VFA about 60%. Increase in number of D45 to 106 CFU/g did not contribute to the improvement of the VFA reduction effect. The D45 of 103 CFU/g did not reduce VFA. These results suggested that the most suitable number of D45 is 105 CFU/g.
