Effect of cereal soaking and carbohydrase supplementation on growth, nutrient digestibility and intestinal microbiota in liquid-fed grow-finishing pigs

Alberto Torres-Pitarch,Peadar G Lawlor,Pierre Cozannet,Paul Cormican,Tomas Ryan,Gillian E Gardiner,Fiona Crispie,Mary Rea,John V O’Doherty

doi:10.1038/s41598-020-57668-6

Abstract

Soaking the cereal fraction of a liquid diet prior to feeding (Csoak), and/or carbohydrase enzyme supplementation (ENZ) are likely to modulate both feed and intestinal microbial populations and improve feed efficiency (FE) in pigs. To test this hypothesis, a total of 392 grow-finisher pigs (~33.4 kg, 7 pigs/pen) were randomly allocated to 4 treatments in a 2 × 2 factorial arrangement for 70 days as follows: (1) fresh liquid feed (Fresh); (2) Cereal soaked liquid feed (Soak); (3) Fresh + ENZ and (4) Soak + ENZ. An interaction between ENZ and Csoak was found for average daily gain (ADG) during the growing phase (day 0 to 21; P < 0.05) where pigs fed the Soak + ENZ diet had higher ADG than pigs fed the Fresh + ENZ diet. No treatment effect was found for ADG thereafter. Enzyme supplementation increased total tract nutrient digestibility (P < 0.05) and reduced caecal VFA concentrations (P < 0.05) but did not improve pig growth or FE. Both Csoak and ENZ modulated intestinal microbiota composition; increasing abundance of bacterial taxa that were negatively correlated with pig growth and reducing abundance of taxa positively correlated with pig growth and caecal butyrate concentration. In conclusion, both strategies (Csoak and ENZ) improved nutrient digestibility in pigs and modulated intestinal microbiota composition.

Highlights

Soaking the cereal fraction of a liquid diet prior to feeding (Csoak), and/or carbohydrase enzyme supplementation (ENZ) are likely to modulate both feed and intestinal microbial populations and improve feed efficiency (FE) in pigs
These endogenous enzymes are activated when they come into contact with water and soaking feed prior to feeding has been suggested as a strategy to increase nutrient digestibility in pigs[24,25,26]
Soaking only the cereal fraction of liquid diets prior to feeding (Csoak) may be a useful strategy to improve the microbial quality and nutritional value of pig feed without reducing it’s free amino acids (AA) content, the latter being supplied in the balancer fraction which is only incorporated into the diet immediately before feeding

Summary

Introduction

Soaking the cereal fraction of a liquid diet prior to feeding (Csoak), and/or carbohydrase enzyme supplementation (ENZ) are likely to modulate both feed and intestinal microbial populations and improve feed efficiency (FE) in pigs. Soaking only the cereal fraction of liquid diets prior to feeding (Csoak) may be a useful strategy to improve the microbial quality and nutritional value of pig feed without reducing it’s free AA content, the latter being supplied in the balancer fraction (containing soybean meal, synthetic AA, minerals and vitamins) which is only incorporated into the diet immediately before feeding Both strategies, namely Csoak and supplementation with a carbohydrase enzyme complex (ENZ), may release substrates for use by microbes present in the liquid feed as well as by those in the gastrointestinal tract (GIT) of the pig. Correlations between growth parameters, intestinal VFA concentrations and the relative abundance of microbial taxa found to be differentially abundant due to treatment (Csoak and ENZ) were conducted to find associations between growth parameters and microbial activity

Objectives

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Results

Discussion

Conclusion