Annual variation in the gut microbiota of captive adult spotted seals, Phoca largha

Abstract

ABSTRACT This study monitored monthly variations in the gut microbiota of three captive adult spotted seals from October 2021 to September 2022. Fecal samples were collected regularly, and 16S rRNA sequencing was used for analysis. A total of 5,502,711 raw sequence reads were generated, revealing 11,978 Amplifying Subsequence Variants across different classification levels. Firmicutes and Proteobacteria were dominant, showing consistent patterns with varying relative abundances over time, indicating stability with seasonal variations. Alpha and beta diversity analyses showed significant variations, with higher diversity in May and June and notable changes between spring and autumn. Intriguingly, nonendemic Proteobacteria were present, suggesting external influences such as interactions with zookeepers or exposure to public programs. Long-term monitoring of microbial communities in captive marine mammals is crucial for understanding impacts from diet, medical history, and enclosure conditions, optimizing their health and wellbeing. This research highlights the importance of microbiota monitoring for managing captive marine mammal health.