SOME BACTREOLOGICAL AND HISTOPATHOLOGICAL STUDIES ON SHELL DISEASED OF CRAB

Mohamed E. Abou El-Atta; Sakr F.S.

and Mohamed M. El-Tantawy

Department of Fish Health and Management, Central Laboratory for Aquaculture Research, Agricultural Research Center, Ministry of Agriculture, Egypt.

Received 18/ 8/ 2013

Accepted 19/ 9/ 2013

Abstract

The study was conducted on hundred and fifty crab gathered from Suez Canal-El kantarah region, Ismailia governorate, Egypt. The clinical examination were recorded in situ, primarily showed swimming lazy, and when it walk toward the shore it unable to move, the swimming legs sometimes loss reflex and paralyzed with lost of one or two segments (propodus and dactyle), the eye stalks in some cases found destructed or unable to retract. Brownish or blackish spots distributed on the dorsal surface of the shell ranged from 1 or 2 mm up to 2-3 cm. In some cases, the spots fused to each other, so that the lesion expanded onto larger areas on different parts of the exoskeleton mostly the dorsal surface than the ventral. Postmortem examination revealed presence of gray black coloration of the gills. Bacteriological examination and identification was performed and resulted in 125 isolates of Vibrio alginolyticus by percentage of 49.02 %, 95 isolates of Vibrio parahemolyticus by percentage of 36.25% and 35 isolates of Aeromonas hydrophyla by percentage of 13.72 %. The antibacterial activity of lactobacillus acidophilus against the isolates strains resulted in inhibition zone 16, 14, and 12 mm diameter while the hemolymph inhibition zone was 12, 17, and 15 against V. alginolyticus, V. parahemolyticus and A. hydrophila respectively. The histopathological findings were described in details.

Key word: Crab, shell disease, bacteria, Egypt.