Active bacterial communities of pig fecal microbiota transplantation suspension prepared and preserved under different conditions.

Although fecal microbiota transplantation (FMT) has become a research hotspot, studies on comparison of the active fecal bacteria suspension under different preparation conditions are limited. This study investigated the abundances of active bacterial community in pig FMT suspension that produced under different oxygen concentrations or cryopreservation conditions. Fecal samples from a Landrace × Yorkshire sow were used to prepare fecal bacteria suspension under the anaerobic (AN group) and aerobic conditions (AE group), respectively. And then half of the anaerobic fecal bacteria suspension was cryopreservation in - 80 °C (AN-CR group) for 1 week. The microbial RNA in the fecal bacteria suspension was extracted before and after cryopreservation, and reverse transcribed into cDNA. MiSeq sequencing 16S rRNA gene of bacterial cDNA showed that the bacterial diversity in the AN group was significantly higher than that in the AE group. Comparing with the sows' fecal sample, the relative abundances of Lactobacillus johnsonii, Lactobacillus coleohominis and Parabacteroides merdae in AN, AE and AN-CR groups were reduced. The short-term cryopreservation had low impact on the structure of the active bacterial community in the fecal bacterial suspension. These results suggest that fecal bacteria suspension can be better prepared under strict anaerobic condition, and that fecal bacteria suspension can be cryopreserved in - 80 °C for a short time.