Intestinal microbiota disturbance affects the occurrence of African swine fever.

Intestinal microbiota not only participates in the digestion and absorption of nutrients, but also plays an important role in regulating host metabolism and health. The current study aimed to explore the intestinal microbiota characteristics in pigs infected with African swine fever. Below the same term, fresh fecal samples of sick and healthy pigs were collected. Primers were designed and PCR was extracted based on the 16S rDNA gene of bacteria by Illumina NovaSeq sequencing platform. The results showed that the bacterial alpha diversity index of healthy pigs was significantly higher than that of sick pigs (p < 0.05). On the phylum taxa, dominant bacteria more than 98.5% in the two groups are composed of Firmicutes, Spirobacteria, and Bacteroides, of which the abundance of Firmicutes and Bacteroidetes decreased and Spiricobacteria increased extremely significant in sick pigs (p < 0.01). On the genus taxa, the relative abundance of Oscillospira, Streptococcus and Roseburia decreased significantly (p < 0.05). Most notably, Treponema performed excellently in distinguishing pigs infected with African swine fever with the abundance increased extremely significantly (p < 0.01). In conclusion, African swine fever could alter the abundance of dominant bacteria in pigs, and Treponema may be one of the important inducers for swine pathogenicity. HighlightsThe bacterial population composition in sick pigs and healthy pigs was basically similar, but the relative abundance of dominant bacteria was significantly difference.ASF could alter the abundance of dominant bacteria in pigs, and Treponema may be one of the important inducers for swine pathogenicity.These results will provide further evidence for the ASF infection in local pig farms and provide reference for their microecological control, which has important practical significance and social value for effective control of ASF, stability of pig production and guarantee of market supply.

Different Intestinal Microbiota with Growth Stages of Three-Breed Hybrid Pig.

The changes of intestinal microbiota are closely related to the growth and development of animals. The current study is aimed at exploring the composition of the microbial community of pigs at different growth stages. Fresh fecal samples of three-breed hybrid pigs at three developmental stages (60, 120, and 180 days of age) were collected. The microbial composition was analyzed based on the 16S rDNA gene of bacteria Illumina NovaSeq sequencing platform. The results showed that the intestinal microbiota of pigs was distributed in 22 phyla, 46 classes, 84 orders, 147 families, and 287 genera. Firmicutes, Bacteroides, Spirochaetae, Proteobacteria, and Actinobacteria were the dominant phyla. Lactobacillus, Streptococcus, SMB53, Oscillospira, and Prevotella were the dominant genera. Among them, the abundance of Lactobacillus and SMB53 increased first and then decreased, while the change of Oscillospira was opposite. In addition, the abundance of Streptococcus increased while that of Prevotella decreased gradually. Moreover, with the increase of time and body weight, the microbial diversity showed a decreasing trend. In conclusion, the intestinal microbial composition of the three-breed hybrid pigs was relatively stable during the fattening stage, but there were significant differences in abundance.

Bacterial Diversity in the Intestinal Mucosa of Dysbiosis Diarrhea Mice Treated with Qiweibaizhu Powder.

The current research tried to explore the effect of Qiweibaizhu powder (QWBZP) on the bacterial diversity and community structure of the intestinal mucosa of dysbiosis diarrhea mice and provide a scientific basis for the efficacy of QWBZP on antibiotic-induced diarrhea. A dysbiosis diarrhea mouse model was constructed with broad-spectrum antibiotics through a mixture of cephradine capsules and gentamicin sulfate (23.33 mL·kg-1·d-1). Intestinal mucosa was collected, and DNA was extracted from each group. The bacterial characteristics in intestinal mucosa were analyzed by MiSeq sequencing based on the 16S rRNA sequencing platform. There were no significant differences in alpha diversity indices among the three groups. The sample distributions in both the normal and QWBZP groups were relatively concentrated, and the distance among individuals was close. However, an opposite result was obtained in the model group. Furthermore, the composition and abundance of species were similar between the normal group and the QWBZP group at both the phylum and genus levels. After treatment with QWBZP, the abundance of Lactobacillus increased, and Proteobacteria decreased, and the Firmicutes/Bacteroidetes ratio decreased to a normal level. Our results indicate that QWBZP can help repair mucosal bacterial structure and recover mucosal microbiota. Specifically, QWBZP increased the abundance of Lactobacillus and Bacteroidales S24-7 group norank.

Diversity of bacterial lactase genes in intestinal contents of mice with antibiotics-induced diarrhea.

AIM: To investigate the diversity of bacterial lactase genes in the intestinal contents of mice with antibiotics-induced diarrhea. METHODS: Following 2 d of adaptive feeding, 12 specific pathogen-free Kunming mice were randomly divided into the control group and model group. The mouse model of antibiotics-induced diarrhea was established by gastric perfusion with mixed antibiotics (23.33 mL·kg-1·d-1) composed of gentamicin sulfate and cephradine capsules administered for 5 days, and the control group was treated with an equal amount of sterile water. Contents of the jejunum and ileum were then collected and metagenomic DNA was extracted, after which analysis of bacterial lactase genes using operational taxonomic units (OTUs) was carried out after amplification and sequencing. RESULTS: OTUs were 871 and 963 in the model group and control group, respectively, and 690 of these were identical. There were significant differences in Chao1 and ACE indices between the two groups (P < 0.05). Principal component analysis, principal coordination analysis and nonmetric multidimensional scaling analyses showed that OTUs distribution in the control group was relatively intensive, and differences among individuals were small, while in the model group, they were widely dispersed and more diversified. Bacterial lactase genes from the intestinal contents of the control group were related to Proteobacteria, Actinobacteria, Firmicutes and unclassified bacteria. Of these, Proteobacteria was the most abundant phylum. In contrast, the bacterial population was less diverse and abundant in the model group, as the abundance of Bradyrhizobium sp. BTAi1, Agrobacterium sp. H13-3, Acidovorax sp. KKS102, Azoarcus sp. KH32C and Aeromonas caviae was lower than that in the control group. In addition, of the known species, the control group and model group had their own unique genera, respectively. CONCLUSION: Antibiotics reduce the diversity of bacterial lactase genes in the intestinal contents, decrease the abundance of lactase gene, change the lactase gene strains, and transform their structures.