Association between oropharyngeal microbiome and weight gain in piglets during pre and post weaning life

Abstract

Birth weight and subsequent weight gain is of critical importance in the survival and performance of piglets on a commercial swine farm setting. Oropharyngeal microbiome could influence immunity, and feeding behavior thus impacting health and weight gain. We used 16S rRNA gene sequencing to profile the composition and predicted metabolic functionality of the oropharyngeal microbiota in 8 piglets (4 with a birthweight ≤ 1.0 kg and 4 with a birthweight ≥ 1.7 kg) at 11, 26, and 63 days of age. We found 9 genera that were significantly associated with average daily gain (ADG) at 11 days (false discovery rate, FDR < 0.05) and 26 days of age (FDR < 0.1), respectively. The microbial functional profile revealed several pathways associated with ADG (FDR < 0.05). Among these, pathways related to degradation of catechols showed a positive association with ADG at 11, 26, and 63 days of age, implying a potential to breakdown the host-derived catecholamines. We also noted that pathways related to the biodegradation of nucleosides and nucleotides increased with ADG during the pre-weaning phase, while those involved in their biosynthesis decreased. Our findings provide insights into the oropharyngeal microbial memberships and metabolic pathways that are involved in a piglet's weight gain. Thus, providing a basis for the development of strategies aimed at improving weight gain in pigs.

Keywords: Average daily gain; Birthweight; Microbiome; Oropharyngeal; Swine.

Fig. 1.. Stacked bar graphs showing the phylogenetic composition of the oropharyngeal microbiota in high birthweight (HBW) vs low birthweight piglets (LBW) at 11, 26, and 63 days of age.

The comparison is made in (A) at phylum level, (B) at family level and (C) at genus level.

Fig. 2.. Principle Coordinate Analysis (PCoA) plots illustrating the phylogenetic composition of the piglets’ oropharyngeal microbial community.

(A) Two dimensional PCoA plot based on unweighted UniFrac distances showing the distribution of the microbiota and 95% distribution ellipses at the 3 time points. (B) Three dimensional PCoA plots based on Bray Curtis distances showing the distribution of the oropharyngeal microbiota in samples collected at 11, 26, and 63 days of age. The symbols represent data from individual piglets and are color-coded by the indicated categories of metadata.

Fig. 3.. Longitudinal analysis of microbial composition.

In (A) is a volatility plot of Shannon diversity showing changes in alpha diversity in high birth weight (HBW) and in low birth weight (LBW) piglets over the study period. In (B–C) are boxplots showing the paired distances in beta diversity of HBW and LBW piglets; (B) between 11 and 26 days of age and (C) between 11 and 63 days of age. The distances are based on the Bray Curtis distance matrices between each subject’s diversity at the given time points.