miRNA‒microbiome correlations in Bos indicus feed efficiency

Area of Science:

• Animal Science
• Microbiology
• Genomics

Background:

• The fecal microbiome is crucial for host metabolism, but its characterization in cattle is incomplete.
• Small RNAs, like microRNAs (miRNAs), can be found in feces and may mediate host-microbe interactions.
• Understanding these interactions is key to improving cattle feed efficiency.

Purpose of the Study:

• To investigate the associations between fecal microRNA expression, gut microbiome composition, and feed efficiency in Nelore bulls.
• To identify specific microRNAs and bacterial taxa related to residual feed intake (RFI).

Main Methods:

• Fecal samples from Nelore bulls with divergent RFI phenotypes were analyzed.
• miRNA sequencing and 16S rRNA gene sequencing were employed to profile host miRNAs and bacterial communities.
• Weighted gene coexpression network analysis (WGCNA) was used to explore miRNA-microbiome interactions.

Main Results:

• Seven fecal microRNAs (bta-miR-27b, bta-miR-30a, bta-miR-126, bta-miR-143, bta-miR-155, bta-miR-205, bta-miR-196a) were upregulated in inefficiently feeding bulls.
• Significant correlations were found between fecal miRNA expression and the abundance of specific bacterial taxa (e.g., Prevotella, Bifidobacterium, Coriobacteriaceae).
• Host miRNAs appear to influence the gut microbiome composition, potentially mediating effects on feed efficiency.

Conclusions:

• Fecal miRNAs and specific gut bacteria are associated with feed efficiency in cattle.
• These findings suggest a role for host-derived miRNAs in modulating the gut microbiome.
• The identified miRNAs and taxa are potential targets for strategies to enhance feed efficiency in cattle.