Animal microbiome最新文献

The rumen microbiota plays a pivotal role in the growth performance of host animals, primarily due to its ability to ferment ingested feed. Hulunbuir sheep exhibited a slow growth rate compared to other local breeds. A deeper comprehension of the development of the rumen bacteria community in Hulunbuir sheep can offer insights into the factors contributing to their slow growth rate. This study utilized metagenomic analysis of rumen content samples from Hulunbuir sheep to investigate the patterns of microbial growth and their relationship with the ADG. The results of the PCoA and enterotype analyses demonstrated that the ruminal bacterial community developed distinct characteristics following weaning. The dominant bacterial phyla in the rumen of Hulunbuir sheep, Bacteroidetes and Firmicutes, exhibited a significant age-related change. At the genus level, while the abundance of dominant bacterial genera changed with the growth of Hulunbuir sheep, Prevotella consistently maintained a high abundance across all age time points. We then examined the effects of age on microbial function by analyzing carbohydrate-metabolizing enzymes and protein-metabolizing peptidases. The abundance of carbohydrate-metabolizing enzymes decreased with growth, while peptidases showed opposite dynamics. Under the current feeding conditions correlation analysis showed that the abundances of Firm-04, CAG-83, and GCA-900,199,385 were negatively correlated with ADG (R<-0.4, p < 0.05), while the abundance of Ga6A1 was positively correlated with ADG (R > 0.5, p < 0.05). In addition, we found 67 MAGs related to ADG, which are capable of secreting carbohydrates-metabolizing enzymes and peptidase. This study uncovers the temporal dynamics of rumen microbiota development during the early to late fattening phase and identifies microbes associated with ADG, which could inform strategies to improve growth and production efficiency.

Background: Heat stress (HS) adversely affects poultry health and productivity. Recently, it has been suggested that the gut microbiota may play a role in host resilience to HS, although the details of its mechanism remain unclear. Here, the heat tolerance-related effects of dietary supplementation of compost fermented by the thermophile Bacillaceae were explored using a laying hen model (601,474 hens in total).

Results: In a field study conducted during the summer (maximum temperatures of approximately 35 °C) in eleven hen houses, oral administration of the compost extract resulted in a statistically significant reduction in mortality. Difference-in-differences analysis revealed that the abundances of the genera Lachnospiraceae NK3A20 group, Enterococcus, Ruminococcus 2, Blautia, Lactobacillus, Christensenellaceae R-7 group, and Tyzzerella 4 were significantly increased by compost administration, whereas those of the Prevotellaceae NK3B31 group, Prevotella 9, Romboutsia, Turicibacter, and Escherichia-Shigella were significantly reduced. In addition, to evaluate the relationship between short-chain fatty acids (SCFAs) metabolic profiles and the gut bacterial population, factor analysis combined with feature selection based on multiple machine learning (ML) algorithms was performed. The resulting optimal structural equation model suggested that compost administration led to increases in the levels of the SCFAs acetate and butyrate, as well as decreases in the levels of the genera Romboutsia and Turicibacter.

Conclusion: Oral administration of thermophile-fermented compost to laying hens alleviated HS-induced mortality. Integrative computational evaluations further revealed that the reduction in mortality was linked to structural changes in the gut microbiota composition and SCFA concentrations.