Biology subjects

Uddin, W.

Publications and source records attributed to Uddin, W..

3 recordsLinked to original sources

bioRxiv2025

Ecological dynamics of the Atlantic salmon gut microbiota across developmental phases and geographic regions

The gut microbiota is vital to host health, yet the relative influence of host traits and environmental factors on fish gut microbiota dynamics remains underexplored. We investigated the ecological dynamics of Atlantic salmon (Salmo salar) gut microbiota, by analysing 847 samples from wild and farmed salmon across diverse geographic regions, developmental phases, and associated diet and environmental microbiota. Farmed salmon exhibits reduced microbial diversity and distinct community composition with increased Firmicutes and reduced Proteobacteria compared to wild salmon. Microbial diversity declined with advancing developmental phases notably due to reduced Proteobacteria and expanded Mycoplasma. Diet was the primary contributor ([~]23%) to farmed salmon microbiota, with environmental inputs varying by region and phase. These findings highlight the importance of aquaculture practices guided by microbiota insights, while emphasize the need to preserve microbial diversity in wild populations to enhance resilience against environmental pressures, contributing to both sustainable farming and conservation strategies.

microbiology↗

bioRxiv2024

Prevalence and diversity of Helicobacter species in captive wild carnivores, and their implications for conservation management of endangered species

Helicobacter species colonize the gastrointestinal tract of various hosts, and have always been of interest due to their potential zoonotic transmission and impact on health of humans and animals. Comprehensive studies involving wild animals from different locations are lacking, hindering our understanding of their natural host range, prevalence, and genetic diversity. Here we investigated the prevalence and genetic diversity of Helicobacter species in thirteen wild carnivore species across twenty-two zoos and rescue centers in India by targeting partial 16S rRNA gene. We used sequences obtained from positive samples for phylogenetic analysis, and further evaluated factors influencing Helicobacter prevalence with generalised linear mixed models. We analysed 985 faecal samples of which 286 (29%) tested positive for Helicobacter, spanning all the host species included in this study. Helicobacter prevalence is strongly related to host species and location, and varied from 7.3% in common leopard to 80% in Indian fox. Phylogenetic analysis identified 59 unique genotypes clustered into 11 groups of three major Helicobacter types: enterohepatic, gastric, and unsheathed. Diverse Helicobacter species associated with diseases in humans and domestic animals were observed, such as H. canis, H. bilis, along with several novel strains/ species which require formal classification. Overall, this study highlights the wide occurrence and high genetic diversity of Helicobacter species in captive wild carnivores in India. Our findings underscore the need for regular health assessments in captive facilities to monitor Helicobacter infections, which could impact the health and management of endangered species. Future research should explore Helicobacter presence in biotic and abiotic factors in zoo and free-ranging populations following One Health approaches.

microbiology↗

bioRxiv2021

Evidence of MHC class I and II influencing viral and helminth infection via the microbiome in a non-human primate

Until recently, the study of major histocompability complex (MHC) mediated immunity has focused on the direct link between MHC variability and susceptibility to parasite infection. However, MHC genes can also influence host health indirectly through the sculpting of the bacterial community that in turn shape immune responses. We investigated the links between MHC class I and II gene variability gut microbiome diversity and micro- (adenovirus, AdV) and macro- (helminth) parasite infection probabilities in a wild population of non-human primates, mouse lemurs of Madagascar. This setup encompasses a plethora of underlying interactions between parasites, microbes and adaptive immunity in natural populations. Both MHC classes explained shifts in microbiome composition and the effect was driven by a few select microbial taxa. Among them were three taxa (Odoribacter, Campylobacter and Prevotellaceae-UCG-001) which were in turn linked to AdV and helminth infection status, evidence of the indirect effect of the MHC via the microbiome. Our study provides support for the coupled role of MHC variability and microbial flora as contributing factors of parasite infection. Author summaryThe selective pressure of the major histocompatibility complex (MHC) on microbial communities, and the potential role of this interaction in driving parasite resistance has been largely neglected. Using a natural population of the primate Microcebus griseorufus, we provide evidence of two outstanding findings: that MHCI and MHCII diversity shapes the composition of the gut microbiota; and that select taxa associated with MHC variability predicted adenovirus and helminth infection status. Our study highlights the importance of incorporating the microbiome when investigating parasite-mediated MHC selection.

evolutionary biology↗