ISOLATION, IDENTIFICATION, AND ANALYSIS OF PATHOGENIC BACTERIA IN MONOPTERUS ALBUS FRY CULTURE

To investigate the etiology of disease outbreaks during the breeding of <italic>Monopterus albus</italic> fry in Xiantao City, Hubei Province, diseased rice-field eels were sampled from the Hubei <italic>Monopterus albus</italic> Industrial Technology Research Institute Co., Ltd. Pathogen identification was conducted through bacterial isolation, sequencing, and an animal reintroduction experiment. The results revealed that <italic>Aeromonas veronii</italic> was detected in both diseased and surviving rice-field eels, accounting for 52.17% and 35.71% of the pathogenic samples, respectively. Furthermore, isolation and identification of pathogens from the primary feed, <italic>Tubificid worms</italic>, also detected <italic>A. veronii</italic>, suggesting the feed as a potential source of pathogen transmission. The animal reintroduction experiment confirmed that rice-field eels infected with <italic>A. veronii</italic> developed symptoms identical to those observed in natural infections, fulfilling Koch’s postulates. This study identifies <italic>A. veronii</italic> as the primary pathogen responsible for disease in cultured <italic>Monopterus albus</italic> in the Xiantao city. These results provide a theoretical basis for the accurate diagnosis and integrated control of diseases in <italic>Monopterus albus</italic> fry in this region.