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Rumen Microbial Taxa and By-products Associated with Feed Efficiency in Sheep
Growing wethers fed a concentrate- (n=39) or a forage-based (n=38) diet were feed efficiency tested, and rumen samples from the 10% most and least feed efficient within diet were collected for microbial DNA sequencing and volatile fatty acid (VFA) analysis. There were 349 prokaryotic microbial taxa detected. Of those, 33 differed (P≤0.05) with the interaction between diet and efficiency status; 83 differed by diet; and 29 differed by efficiency status. Molar concentrations of propionate and valerate tended (P<0.10) to be affected by the diet and efficiency status interaction. Concentrations of acetate, propionate, and valerate were affected (P<0.001) by diet, and propionate was additionally affected (P=0.032) by efficiency status. Results indicate that key microbial taxa and their VFA by-products may play an important role in diet-dependent regulation of feed efficiency.
Keywords:
Sheep
Rumen microbiome
Feed efficiency
