Effects Of Inhibition Of Intestinal Methanogens On The Microbial Metabolism In Monogastric Animals

Recently, more and more reports draw peoples’ attention to the CH4 because it is a metabolic waste of monogastric animals. It intensifies the greenhouse effect when it is discharged into the atmosphere. CH4 may produce from the feed material, the formation of CH4 may affect body weight by taking part in hosts’ metabolism. This research mainly focused on gut microbial metabolic alterations when methanogen was inhibited. In the current study, in vitro fermentation model was constructed first. Results showed that gas production and VFA accumulation was impacted significantly when methanogen was removed. Then, we used post-weaning piglets as in vivo model to investigate the effects of inhibition of gut methanogens on the concentration of VFA and microbial community composition. Finally, we selected rats as animal model to study the influences of high fat diet and methanogens inhibitor on the cecal microbiota and fat metabolism in C57BL/6J mice.1 Effect of Methanogens inhibitors on the in vitro fermentation of different carbonhydrate substrates by fecal microbiota of pigsPrevious studies found that methane-producing bacteria exist in the intestine of piglets. However, their role had not been well understood. In this study, in vitro fermentation technology was used to investigate the effects of methanogens inhibitors on the in vitro fermentation of different carbonhydrate substrates by fecal microbiota of pigs by using. fresh feces of piglets as inoculums, using FOS, alfalfa, pectin, wheat bran, wheat starch as substrates. We determined the production of gas and CH4 and VFA concentrations. In vitro fermentation results showed that after 36 h fermentation, organic matter correction producing gas (OMCV), gas production reached a total production volume of half time (T1/2), the largest producing gas rate (Rmax), reached maximum production rate of gas the time (Tmax) were significantly affected by substrates (P<0.01); These parameters except OMCV were also significantly affected by the inhibitors(P<0.01). The CH4-producing capability of different substrates were as follows:alfalfa> bran> pectin> FOS> starch.2 Influences of methanogens inhibitor on the feces microbiota and VFA production in ternary pigletThe aim of this study was to investigate the effects of methanogen inhibitor (bromochloromethane, BCM) on the gut microbiota and VFA production in piglets. Eighteen female Duroc X Landrace X Large White piglets were randomly divided into two groups:BCM and Control. BCM was added by oral administration. The experiment lasted 40 days. The body weight of the piglets was recorded every 10 days. At the end of experiment, bacterial communities in feces were detected by denaturing gradient gel electrophoresis (DGGE) and real-time PCR. VFA production in feces was analyzed by gas chromatography. The results showed that BCM had no effect on the average daily gain of piglets. DGGE analysis showed that samples from piglets treated with BCM gathered together, and separated with samples from the control group. However, both the age and BCM treatment had no effect on the numbers of total bacteria and methanogens. The isobutyate proportion in total VFA in feces was significantly decreased (P<0.05) while propionate proportion significantly increased(P<0.05) when piglets were treated with BCM.3 Influences of high fat diet and methanogens inhibitor on the cecal microbiota and fat metabolism in C57BL/6J miceThe aim of this study was to investigate the effects of high fat diet and methanogens inhibitor (BCM) on the gut microbiota and fat metabolism in mice. Thirty two female C57BL/6J mice were randomly divided into four groups:Low fat, Low fat+BCM, High fat and High fat+BCM. BCM was administrated through drinking water. The research lasted six weeks. The body weight of mice was recorded every week. At the end of the experiment, the blood was collected for serum biochemical analysis. Bacterial communities in cecal digesta were analyzed by DGGE and real-time PCR. VFA concentrations in feces were determined by gas chromatography. Expression of fat-related genes in liver was analyzed by using real-time PCR. DGGE analysis showed that samples from mice fed with high fat diet gathered together, and separated with samples from low fat diet group. However, both the fat level in feed and BCM treatment had no effect on the numbers of total bacteria, SRB and methanogens. The acetate proportion in feces was significantly decreased (P< 0.05) when fed high fat diet to mice (P<0.05). BCM treatment significantly increased the propionate proportion (P<0.05). High fat diet significantly increased the levels of High-density lipoprotein cholesterol (HDL-C), Low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TG) in the blood (P<0.05). High fat diet up-regulated the expression of TGH gene (P<0.05). It concluded that high fat diet affected cecal microbiota and fat metabolism of mice, while BCM treatment showed a relative weak effect.