Microbiome network traits in the rumen predict average daily gain in beef cattle under different backgrounding...

Area of Science:

• Animal Science
• Microbiology
• Ruminant Nutrition

Background:

• Backgrounding (BKG) is a critical growth stage in beef cattle.
• The role of the rumen microbiome in BKG performance is not well understood.
• This study investigates the impact of different BKG systems on rumen bacteria and average daily gain (ADG).

Purpose of the Study:

• To assess how different backgrounding (BKG) systems influence rumen bacterial communities.
• To determine the relationship between rumen microbiome composition and average daily gain (ADG) in beef cattle.
• To explore the predictive power of microbiome network traits for cattle growth.

Main Methods:

• 38 weaned calves were assigned to three BKG systems: dry lot (DL), annual cover crop (CC), or perennial pasture (PP).
• Rumen fluid was sampled longitudinally for 16S rRNA gene sequencing to profile bacterial communities.
• Calf weights were recorded to calculate ADG throughout BKG and finishing phases.

Main Results:

• Rumen bacterial communities significantly diverged across BKG systems, with reduced alpha diversity in CC and DL groups.
• Dry lot (DL) calves showed increased Proteobacteria and higher ADG during BKG.
• Perennial pasture (PP) calves exhibited compensatory ADG during finishing, outperforming DL calves.
• Microbiome network traits, like bacterial interaction strength, were better predictors of ADG than specific taxa abundance.

Conclusions:

• Bacterial co-abundance interactions, analyzed via network theory, are superior predictors of beef cattle growth during BKG and finishing compared to individual taxa.
• The backgrounding stage presents a key opportunity for nutritional interventions to enhance rumen microbial interactions and boost cattle productivity.