Identification of gut microbes associated with feed efficiency by daily-phase feeding strategy in growing-finishing pigs.

Abstract

Feed efficiency is one of the most important issues for sustainable pig production. Daily-phase feeding (DPF) is a form of precision feeding that could improve feed efficiency in pigs. Gut microbiota can regulate host nutrient digestion, absorption, and metabolism. However, which key microbes may play a vital role in improving the feed efficiency during DPF remains unclear. In the present study, we used a DPF program compared to a three-phase feeding (TPF) program in growing-finishing pigs to investigate the effects of gut microbiota on feed efficiency. A total of 204 Landrace×Yorkshire pigs (75d) were randomly assigned into 2 treatments. Each treatment was replicated 8 times with 13 to 15 pigs per replicate pen. Pigs in the TPF group were fed with a commercial feeding program that supplied fixed feed for phases I, II, and III, starting at 81, 101, and 132 d of age, respectively, and pigs in the DPF group were fed a blend of adjacent phase feed from 81 to 155 d at a gradual daily ratio and phase III feed from 155 to 180 d of age. Daily feed intake and body weight were recorded by a computerized device in the feeders. Feces and blood samples were collected from 1 pig per replicate at 155 and 180d of age. The results showed that the DPF program remarkably improved the feed efficiency at 155 d (P<0.001) and 180d of age (P<0.001), with a significant reduction of the intake of crude protein (P<0.01), net energy (P<0.001), crude fiber (P<0.001), ether extract (P<0.01), and ash (P<0.001). The daily-phase feeding program increased the abundance of Prevotella copri (P<0.05) and Paraprevotella clara (P<0.05), while it decreased the abundance of Ocilibacter (P<0.05) at 155d of age. The results of correlation analysis indicated that the differentially abundant microbiota communities were closely associated with 20 metabolites which enriched amino acid and phenylalanine metabolism. Our results suggest that 2 key microbes may contribute to feed efficiency during daily-phase feeding strategies in pigs.