Metagenomic Analysis of the Fecal Archaeome in Suckling Piglets Following Perinatal Tulathromycin Metaphylaxis

SIMPLE SUMMARY: The archaeal population, or ‘archaeome’, is comprised of unicellular microorganisms with a distinct biology compared with bacteria and has been shown to be an important component of host-associated microbes. While the impact of antimicrobial administration on gastrointestinal microbiota has been widely evaluated, no metagenomics-based analysis has been performed to assess the impact of an early life antimicrobials intervention on the fecal archaeome in swine. The aim of this study was therefore to investigate the impact of perinatal tulathromycin (TUL) administration on the fecal archaeome composition and diversity in suckling piglets using metagenomic sequencing analysis. Our results suggest that perinatal TUL metaphylaxis seems to have a minimal effect on the gut archaeome composition and diversity in sucking piglets. ABSTRACT: The gastrointestinal microbiome plays an important role in swine health and wellbeing, but the gut archaeome structure and function in swine remain largely unexplored. To date, no metagenomics-based analysis has been done to assess the impact of an early life antimicrobials intervention on the gut archaeome. The aim of this study was to investigate the effects of perinatal tulathromycin (TUL) administration on the fecal archaeome composition and diversity in suckling piglets using metagenomic sequencing analysis. Sixteen litters were administered one of two treatments (TUL; 2.5 mg/kg IM and control (CONT); saline 1cc IM) soon after birth. Deep fecal swabs were collected from all piglets on days 0 (prior to treatment), 5, and 20 post intervention. Each piglet’s fecal archaeome was composed of rich and diverse communities that showed significant changes over time during the suckling period. At the phylum level, 98.24% of the fecal archaeome across all samples belonged to Euryarchaeota. At the genus level, the predominant archaeal genera across all samples were Methanobrevibacter (43.31%), Methanosarcina (10.84%), Methanococcus (6.51%), and Methanocorpusculum (6.01%). The composition and diversity of the fecal archaeome between the TUL and CONT groups at the same time points were statistically insignificant. Our findings indicate that perinatal TUL metaphylaxis seems to have a minimal effect on the gut archaeome composition and diversity in sucking piglets. This study improves our current understanding of the fecal archaeome structure in sucking piglets and provides a rationale for future studies to decipher its role in and impact on host robustness during this critical phase of production.