ASSESSMENT OF AEROMONAS HYDROPHILA BIOFILM AS ORAL VACCINE CANDIDATE AGAINST AEROMONAS INFECTION IN NILE TILAPIA (OREOCHROMIS NILOTICUS)
Loading...
Date
2021
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR
Abstract
Nile tilapia being one of the most potential candidate species for aquaculture stands second in global total fish production. Along with the increased production, intensification of fish culture systems paved the foundation for the incidence of several infectious diseases. Further, these diseases resulted in the huge economic losses to the fish farmers. Among these diseases, Aeromonas hydrophila is the major causative agent and its outbreaks are most common in fresh water fishes. Hence, for treating this disease, antibiotics were predominately used. Due to the increased usage of antibiotics, raised antibiotic resistance in bacteria were found. To cut such complications biofilm vaccines were used. Biofilm of A. hydrophila oral vaccination was used in Nile tilapia fingerlings to evaluate the effect on growth and disease resistance to A. hydrophila. An experimental trail was conducted for 80 days with biofilm, free cell and control diet. Initial 20 days of the experiment was fed with vaccinated feed (Biofilm and Free cell) and remaining 60 days were fed with control diet. At the end of the study, the biofilm vaccinated group showed significantly higher (p < 0.05) SGR, mean weight gain, ADG and PER. When compared with the free cell vaccinated and control groups, the biofilm vaccinated group showed a lower FCR value. Biofilm vaccinated group of fish showed higher RPS (100, 100 and 87.5%) than free cell vaccinated group of fish (16, 27 and 27%) in case of A. hydrophila, A. sobria and A, veronii respectively. The present study concludes that, the biofilm vaccine of A. hydrophila protects the fish against Aeromonas infections caused by A. veronii and A. sobria. Hence, biofilm vaccines proved to have broad spectrum of defence against Aeromonas infections.