Research On The Basic Laws Of Skatole Production And Its Variation With Intestinal Microbial Components In Broilers

Skatole(3-methylindole) is the main degradation of L-tryptophan produced by the intestinal bacteria in the hind gut of monogastric animals, it is a repugnant substance. In this experiment, indole and skatole production in different growth phases and in different intestinal segments are detected to analysis the basic laws of skatole production of broilers, in the meanwhile, molecular biology methods are been used to analysis the variation of the microbial components of ileum, cecum and rectum of broilers, and discover the microbial information of skatole production.In this experiment, indole, sktole, lactic acid and VFA concentrations of the 2-6 weeks old broilers’feces and of 6 weeks old broilers’ileum, cecum and rectum are detected, the PCR-DGGE is used to analysis the microflora structure and the diversity of the content in different intestinal segments of 6 weeks old broilers, the RT-qPCR is used to analysis total flora counts, E. coli counts, Lactobacillus counts and Bifidobacterium counts in different intestinal segments. The results show that:(1) The basic laws of skatole production in broilers:indole, skatole, lactic acid and VFA concentrations in feces are increased by the week of age growing. Indole and skatole production of 2 weeks old broilers are highly significant lower than those of 4～6 weeks (P<0.01), indole and skatole production of 3 weeks are highly significant lower than those of 6 weeks. Lactic acid concentration of 2 weeks old broilers is significant lower than that of 6 weeks (P<0.05), there are no significant differences of lactic acid concentration between 3-6 weeks (P>0.05), there are no significant differences of acetic acid between different segments (P>0.05). Skatole and indole concentrations in cecum are highly significant higher than those in ileum (P<0.01), indole concentration in rectum is highly significant lower than cecum (P<0.01), skatole concentration in rectum is significant lower than cecum (P<0.05)(2) The microflora of different intstinal segments in broilers:the microflora diversity index of cecum is highly significant higher than that of ileum, and there are no significant differences of diversity index between rectum and ileum or cecum. The microflora richness of cecum is highly significant higher than that of ileum, and it is significant higher than that of rectum. There are no significant differences of evenness between rectum, ileum and cecum. The similarity between ileum and cecum is the lowest among all intestinal segments, the similarity between ileum and rectum are the highest. Cecum microflora have one specific band, its similarity bacteria is Bacteroides uniformis, cecum and rectum have three common bands, the similarity bacteria are Lactobacillus vaginalis and two Candidatus Arthromitus sp..(3) The microflora counts of different intstinal segments in broilers:The total flora counts of cecum are highly significant higher than ileum, the total flora counts of rectum are higher than ileum, but not significantly. E.coli counts of cecum are highly significant higher than ileum, and there are no significant differences of E. coli counts between rectum and ileum or cecum. There are no significant differences of Lactobacillus counts between different intestinal segments (P>0.05). Bifidobacterium counts of rectum are significant higher than rectum, Bifidobacterium counts of ileum are higher than rectum.(4) Skatole production and its variation with intestinal microbial components of broilers: the microflora diversity index is highly significant positive correlation with skatole, indole, lactic acid and acetic acid (P<0.01); the microflora richness is highly significant positive correlation with skatole and acetic acid (P<0.01), it is significant positive correlation with indole and lactic acid. The total flora counts results are highly significant positive correlation with skatole, idole, lactic acid and acetic acid (P<0.01); Lactobacillus counts are significant positive with skatole; Bifidobacterium counts are significant positive correlation with skatole and acetic acid. The author speculates that Bacteroides uniformis, Lactobacillus vaginalis, and two Candidatus Arthromitus sp. are related to the skatole and indole production based on the microflora sequences analysis.To sum up, skatole production is increased by the week of age growing, skatole production is the highest in cecum and lowest in ileum. Skatole production is affected by the intestinal microbial components; microflora diversity index, microflora richness and total microflora counts are positive related to skatole production.