Role of freshwater crayfish Procambarus Clarkii in transmission of motile Aeromonas septicemia to Nile tilapia Oreochromis n (one mark)‎

Abstract EN

A total of 60 Nile tilapia fish Oreochromis niloticus were collected from River Nile (Damietta branch): Weesh El-Hagar village during late summer.

An experimental infection was applied on apparently healthy Nile tilapia (three equal groups) by intramuscular injection of 0.1 ml of 2.4X107 CFU/ml of well identified A.

hydrophila suspension isolated from freshwater crayfish P.

clarkii, while, the third group was injected 0.1 ml of sterile buffered saline .

The clinical picture, morbidity and mortality rates were recorded for 7 days.

The results showed that all injected tilapia died by the end of experiment with a mortality peak on the 3rd day, while the morbidity started to appear by the 2nd day (10%).

The histopathological alterations were recorded and discussed.

This study suggests an epidemiological significance of Aeromonas hydrophila and the role of crayfish in its transmission