The Rumen Microbiome Composition of Raramuri Criollo and European Cattle in an Extensive System.

Area of Science:

• Animal Science
• Microbiology
• Genomics

Background:

• Sustainable beef production requires understanding cattle adaptation.
• Raramuri Criollo (RC) cattle are adapted to harsh environments.
• Their rumen microbiome's role in adaptation is largely unknown.

Purpose of the Study:

• To characterize and compare the rumen microbiome of RC cattle with European (E) breeds and their crosses (E × RC).
• To identify microbial differences associated with RC cattle adaptation.

Main Methods:

• Collected ruminal fluid from 63 cows across dry and rain seasons.
• Isolated DNA for 16S rRNA gene next-generation sequencing.
• Analyzed data using QIIME2 and compared against the SILVA 16S rRNA database.

Main Results:

• Significant differences in beta diversity were observed between RC and E cattle in both seasons.
• Abundant microbial phyla like Planctomycetes, Spirochaetes, and Euryarchaeota showed seasonal variations.
• LEfSe analysis revealed key microbial groups differentiating RC cattle, indicating specialization in fibrous content degradation.

Conclusions:

• RC cattle exhibit a distinct rumen microbiome composition compared to European breeds.
• The identified microbial communities in RC cattle suggest an adaptation to degrade high-fiber diets in challenging conditions.
• These findings support the potential of RC cattle for sustainable beef production systems.