This study aimed to examine the prevalence, serovars, and antimicrobial resistance of Salmonella isolates from broiler chickens in Kagoshima, Japan. A total of 192 flocks and 3071 samples were collected from broiler chickens at local farms in Kagoshima, Japan from 2009 to 2012. Among the tested farms, 49.0% of flocks were positive for Salmonella, and 243 isolates were obtained from 3071 cecal samples (7.9%). All the Salmonella isolates were one of three serovars: S. Infantis (57.6%); (140/243), S. Manhattan (40.3%; 98/243 and S. Schwarzengrund (2.1%; 5/243). The proportion of S. Infantis isolates decreased from 66.0% in 2009 to 50.0% in 2011 but increased to 57.6% in 2012, while the proportion of S. Manhattan isolates significantly increased from 26.4 to 50% from 2009 to 2011, and decreased moderately to 40.9% in 2012. Most of the recovered Salmonella isolates were resistant to three antimicrobials, i.e., streptomycin (95.1%), sulfamethoxazole (91.0%) and oxytetracycline (91.4%). In contrast, all Salmonella strains were susceptible to chloramphenicol. Comparison of this study to previous studies of the antimicrobial susceptibility of Salmonella isolates showed that: the percentage of antibiotic-resistance isolates increased dramatically for two antibiotics, ampicillin (from 22.4 to 55.1%) and cefotaxime (from 9.1 to 52.7%). In contrast, the percentage of ofloxacin-resistant isolates decreased across the three survey periods, from 20.8% in 2004–2006 to 1.6% in the present study period (2009–2012). In addition, S. Infantis exhibited a variety of resistance to antimicrobials examined from sensitive to resistance to eight antimicrobials. Multidrug resistance to more than 6 six antimicrobials was detected in 113 (46.5%) of the isolates, and most of them were S. Manhattan. There was a marked change in the serovars and antimicrobial resistance profiles of the Salmonella isolates in this study compared to those in previous studies. The percentage of S. Manhattan isolates increased as did the percentages of ampicillin- and cefotaxime-resistant isolates.

Ciguatera fish poisoning (CFP) is one of the most frequently reported seafood poisoning diseases. It is endemic to the tropical region and occurs most commonly in the regions around the Pacific Ocean, Indian Ocean, and Caribbean Sea. The principal toxins causing CFP are ciguatoxins (CTXs). In the Pacific region, more than 20 analogs of CTXs have been identified to date. Based on their skeletal structures, they are classified into CTX1B-type and CTX3C-type toxins. We have previously reported species-specific and regional-specific toxin profiles. In this study, the levels and profiles of CTXs in fish present in the tropical western Pacific regions were analyzed using the liquid chromatography–tandem mass spectrometry (LC–MS/MS) technique. Forty-two fish specimens, belonging to the categories of snappers, groupers, Spanish mackerel, and moray eel, were purchased from various places such as Fiji, the Philippines, Thailand, and Taiwan. Only the fish captured from Fijian coastal waters contained detectable amounts of CTXs. The toxin levels in the fish species found along the coastal regions of the Viti Levu Island, the main island in Fiji, and the toxin profiles were significantly different from those of the fish species present in other coastal regions. The toxin levels and profiles varied among the different fish samples collected from different coastal areas. Based on the toxin levels and toxin profiles, the coast was demarcated into three zones. In Zone-1, which covers the northern coast of the main island and the regions of the Malake Island and Korovau, CTXs in fish were below the detection level. In Zone-2, CTX3C-type toxins were present in low levels in the fish. CTX1B-type and CTX3C-type toxins co-occurred in the fish present in Zone-3. The toxin profiles may have reflected the variation in Gambierdiscus spp.