Surveillance of intestinal pathogens and their virulence genes as well as antibiotic susceptibility in bivalve shellfish and the aquatic environment in Taiwan

• Main Authors: CHEN, YUEH-WEN, 陳岳汶
• Other Authors: Bing-Mu Hsu
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/472bz9

碩士 === 國立中正大學 === 地球與環境科學研究所 === 105 === Shellfish is one of the most important aquaculture product in Taiwan. The cleanness of shelter water of aquaculture farms and surrounding water bodies are critical to the health of shellfish and human. The contamination of pathogens in waterbody is a potential threat to the sea animals and human beings. We aimed to survey the pathogens in the offshore shellfish farms and the surrounding waterbodies, namely major harbors of Taiwan, offshore aquaculture farming areas, and wastewater from livestock farm around Puzi River. The shellfish collected from seafood markets and offshore aquaculture areas were also tested. The polymerase chain reaction(PCR) was employed to detect the pathogenic bacteria of shellfish and environmental water bodies. Our results indicated the Bacillus cereus and MRSA were the most detective pathogens in water bodies, suggesting a potential threat of environmental waterbodies to human health. The antibiotic resistance of pathogens and their phylogenetic relationship were also investigated by ERIC-PCR. Data showed high rates of Bacillus cereus contained virulence genes (41%,18/44). In the study of antibiotic resistance test, results showed Bacillus cereus was resistant to Ampicillin and sulfamethoxazole / Trimethoprim. Data of ERIC-PCR revealed that the species of Bacillus were very diverse, forming five groups and 43 types in of phylogenetic tree in the Bacillus. In virulence gene studies of MRSA, results showed that all tested MRSA carried the exfoliative toxin gene (etb). Moreover, high rates of MRSA were antibiotic resistant (12/15). Results of phylogenetic analysis indicated that there is a very high degree of similarity which correlated to the locations in the DNA sequencing of MRSA. This study concluded that most environmental Bacillus cereus are virulent, which the transmission pathway is needed to be aware of. With high degree of resistant rates to antibiotic, infection of MRSA was dangerous. More studies are needed to surveil the evolutions of pathogens regarding their virulence genes and antibiotic resistances.