Vibrio species infections to oreochromis niloticus and mugil cephalus: sodium chloride tolerance pathogenicity, serological relatedness and antibiograms sensitivity of recovered vibrios

ABSTRACT

Vibrio species were recovered from 40.00% of examined fish in both Qarun and Manzala lakes. The isolation was 37.50% from Mugil cephalus and 42.50% Oreocliroinis niloticus. Recovered Vibiros were V. anguillarum biotype c, V. ordalii, V. damsela and V. vulnificus group 2. A concentration of 4-9% sodium chloride in the culture media was helpful in the isolation of Vibrio species. Septicaemic picture of intraperitoneally inoculated Oreochromis nhloticus with different Vibrio species occurred within 1-week post - infection. Active immunization of O. niloticus with formalized whole cultures prepared from recovered vibrios resulted in diferent titres with the highest recorded one against V. angullarurn biotype C. serological relatedness among different vivrios and their corresponding antisera showed that antisera of V. anguillaruni biotype C was able to cross react with other vibrio species. Sensitivity of recoverd vibrios was recorded to chioramphenicol, colistin sulphate, nitrofuratntion, oxytetracycline and tetracycline