Molecular markers and histopathological effects of some fish parasites, in Egypt.

Abstract

This work is designed to describe the helminth parasites infecting the following Nile fish: Clarias lazera, Oreochromis niloticus and Tilapia zillii collected from fish markets and fishermen in three Governorates (El-Kaliobiya, El-Sharkia and El-Giza) in Egypt during the period from April 2011 to July 2013. Total of 685 fish were examined from three different sampling sites. Clarias lazera fish were infected with helminthes for prevalence 46.73 %, while 2.8 % and 2.07 % of the examined Oreochromis niloticus and Tilapia zillii fish were infected, respectively. The recorded helminth parasites are summarized as follows: Digenea: Orientocreadium batrachoides, Eumasenia aegyptiacus and Astiotrema sudanensis. Cestoda: Polyonchobothrium clarias. Nematoda: Procamallanus laeviconchus. The histolopathological studies of the Clariaslazera fish intestine revealed that Orientocreadiumbatrachoideswas recognized at the submucosa causing necrosis in villi and hemorrhages. Degenerative changes in the submucosa, muscularis and serosa layers appeared clearly. Moreover, parasitophrous vacuoles around the parasite was recognized. Necrosis in the submucosa layer was detected. In the present study, the commonest parasite (Orientocreadium batrachoides) is chosen for examination by using the scanning and transmission electron microscopes. Biochemical markers such as protein fractions and isozymes (α-Esterase, ADH and MDH) are used to compare between normal and infected Clariaslazera fish. Keywords:Helminth parasites, Orientocreadium batrachoides, Eumasenia aegyptiacus, Astiotrema sudanensis, Polyonchobothrium clarias, Procamallanus laeviconchus, TEM, SEM, biochemical markers, protein, α-Esterase, ADH, MDH.