Enteric Red Mouth disease and its causative bacterium, Yersinia ruckeri, in Indian Major Carps from culture ponds in Andhra Pradesh, India

Abstract

During the present investigation, studies were carried out to investigate the outbreak of Redmouth disease in culture ponds situated at Krishna, West Godavari and East Godavari districts of Andhra Pradesh. Enteric Red Mouth disease or Yersiniosis is a serious infectious bacterial disease, sometimes responsible for causing severe economic loss to fish farming industry. The disease is clinically characterized by symptoms like bleeding at the base of fins, inside and around mouth, bilateral exophthalmia with or without haemorrhage, and per-ocular and peri-oral haemorrhages. In the present study, live or moribund fish showing lesions similar to enteric redmouth disease were collected and the causative agent was isolated by culture techniques. Bacterial identification was carried out by conventional biochemical methods and molecular polymerase chain reaction. DNA extracted from isolated pathogen was subjected to PCR amplification with a pair of Y. ruckeri specific primers. The PCR product was run on 1.5% agarose gel electrophoresis and positive bands with a molecular size of approximately 500bp were detected. It is similar to that given for PCR products with primers specific for Y. ruckeri.