Columnaris disease has recently emerged as a concern for black carp (Mylopharyngodon piceus), an economically important aquaculture species in northern Vietnam. This study investigated the disease outbreaks from five affected farms. A total of 47 naturally diseased fish were sampled for bacterial isolation and identification.
View Article and Find Full Text PDFWidespread distribution of a highly pathogenic Edwardsiella ictaluri strain in farmed tilapia in northern Vietnam has recently been reported. The subsequent investigation noticed a disease outbreak occurred at five nearby tilapia farms with floating cages, in which the clinical signs of both edwardsiellosis and columnaris diseases were observed on the same infected fish and caused 65% to 85% fish mortality. Naturally diseased fish (n = 109) were sampled from the five infected farms for bacterial identification and conducting challenge tests.
View Article and Find Full Text PDFWhite grub metacercariae were found in the livers and kidneys of diseased specimens of an introduced channel catfish, Ictalurus punctatus (Rafinesque), in Vietnam. Based on morphological features and 28S rDNA sequence analysis, the isolated metacercariae were identified as Dollfustrema bagarii (Digenea: Bucephalidae) Moravec & Sey. Histopathological examination shows that encysted metacercariae can change the tissue structure of the infected organs and is often accompanied by haemorrhaging and the presence of eosinophilic granular cell infiltration.
View Article and Find Full Text PDFEdwardsiella ictaluri is an emerging bacterial pathogen that affects farmed tilapia (Oreochromis spp.). This study reports the widespread presence of E.
View Article and Find Full Text PDFThe study aims to evaluate the infection prevalence, virulence gene distribution and antimicrobial resistance of associated in diseased outbreaks of cultured freshwater fish in Northern Vietnam. The confirmed were screened for the presence of the five pitutative-virulence genes including aerolysin (), hemolysin (), cytotonic enterotoxin (), heat-labile cytotonic enterotoxin (), and heat-stable enterotoxin (), and examined the susceptibility to 16 antibiotics. A total of 236 isolates were recovered and confirmed from 506 diseased fish by phenotypic tests, PCR assays, and , sequenced analyses, corresponding to the infection prevalence at 46.
View Article and Find Full Text PDFSamples of Haplorchis taichui and Haplorchis pumilio of different life-stages (cercariae, metacercariae and adults) and from different host species (snail, fish, dog, cat and human) were collected in Nghe An and Nam Dinh Provinces in Vietnam. Samples from Thailand were available for comparison. All adults and metacercariae were initially identified using morphological criteria.
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