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Kittiwan, N.

Publications and source records attributed to Kittiwan, N..

2 recordsLinked to original sources

Investigation of swine caecal microbiomes in the northern region of Thailand

IntroductionThe northern region of Thailand serves as a crucial area for swine production, contributing to the global food supply. Previous studies have highlighted the presence of foodborne pathogens originating from swine farms in this region, posing a threat to both human and animal health. Gap statementMultiple swine pathogens have been studied at a species level, but the distribution and co-occurrence of pathogens in agricultural swine has not been well established. AimOur study employed the intestinal scraping technique to directly examine the microorganisms interacting with the swine host. MethodologyWe used shotgun metagenomic sequencing to analyse the caecal microbiomes of swine from five commercial farms in northern Thailand. ResultsSwine caecal microbiomes contained commensal bacteria such as Bifidobacterium, Lactobacillus, and Faecalibacterium, which are associated with healthy physiology and feed utilisation. We also identified multiple pathogenic and opportunistic bacteria present in all samples, including Escherichia coli, Clostridium botulinum, Staphylococcus aureus, and the Corynebacterium genus. From a One Health perspective, these species are important foodborne and opportunistic pathogens in both humans and agricultural animals. Antimicrobial resistance genes were also detected in all samples, specifically conferring resistance to tetracycline and aminoglycosides which have historically been used extensively in swine farming. ConclusionThe findings further support the need for improved sanitation standards in swine farms, and additional monitoring of agricultural animals and farm workers to reduce contamination and improved produce safety for human consumption.

microbiology↗

Non-serotype 2 isolates from healthy pigs are a potential zoonotic reservoir of Streptococcus suis genetic diversity and antimicrobial resistance

Streptococcus suis is a leading cause of bacterial meningitis in SE Asia, with frequent zoonotic transfer to humans associated with close contact with pigs. A small number of invasive lineages are responsible for endemic infection in the swine industry causing considerable global economic losses. A lack of surveillance and a rising trend in clinical treatment failure has raised concerns of growing antimicrobial resistance (AMR) among invasive S. suis. The source-sink dynamics between healthy and disease isolates is poorly understood and, in this study, we sample and sequence a collection of isolates predominantly from healthy pigs in Chiang Mai province, Northern Thailand. Pangenome comparisons with a selection of invasive serotype 2 isolates identified increased genetic diversity and more frequent AMR carriage in isolates from healthy pigs. Multiple antimicrobial resistance genes were identified conferring resistance to aminoglycosides, lincosamides, tetracycline and macrolides. All isolates were non-susceptinle to three or more different antimicrobial classes, and 75% of non-serotype 2 isolates were non-susceptible to 6 or more classes (compared to 37.5% of serotype 2 isolates). Antimicrobial resistance genes were found on integrative and conjugative elements (ICE) previously observed in other species, suggesting mobile gene pool which can be accessed by invasive disease isolates. Significance statementThe zoonotic pathogen Streptococcus suis causes respiratory disease in pigs and is among the most common causative agents of human clinical bacterial meningitis in SE Asia. We collected isolates from farmed healthy pigs in Northern Thailand, representing a source population from which invasive isolates have recently emerged - linked to the pork production industry. Pangenome characterisation of the isolates revealed a reservoir of genetic diversity and antimicrobial resistance suggesting that One Health approaches may be beneficial in tackling the increase in antimicrobial resistance.

microbiology↗