bovine gut metagenome Metagenome. bovine gut metagenome

By-products from the food processing industry, such as brans, middlings, oilseed products, and beet pulp, have received special attention in ruminant nutrition lately. However, information regarding the effects of by-product-rich diets on the rumen microbial ecosystem is still limited; especially when feeding them as sole concentrate source to cattle. Particularly, the high phosphorus (P) content in by-products is attractive from an environmental point of view to reduce inorganic P supplementation in diets for cattle and consequently minimize P excretion in manure. However, this P occurs mainly in the form of phytate-P of low bioavailability and ruminal degradation of phytate-P is often incomplete. Therefore, often inorganic P is added to cattle rations although containing sufficient total P. This study used a rumen simulation technique to evaluate the effects of soaking of by-product rich concentrate (BPC) in 5% lactic acid (LA; v/v) on the rumen microbiota, predicted metagenome, fermentation characteristics and nutrient degradation without or with supplemented P. Fermenter fluid was collected for analyses of short-chain fatty acids, fermentation gases, redox potential and microbiota and feed residues for calculation of nutrient degradation from experimental day 6 to 10, respectively. The microbiota composition was assessed using paired-end Illumina MiSeq sequencing of the V3-5 region of the 16S rRNA gene.