On The Histopathological and Physiological Effects of Helminth Parasites On Clarias lazera (Cuv and Val, 1840) from Jebel Aulia Reservoir

Abstract

An extensive search for histopathological and physiological effects of helminthic parasites was carried out on 100 freshwater fishes Clarias lazera collected fiom Jebel Aulia reservoir on the White Nile south of Khartoum(45Km)in the period 2010-2013 . The physiological investigation involved measurements of blood parameters, this revealedthat the increase in haemoglobin concentration (Hbg/dl) , white blood count ( 1000/mma ) ,red blood corpuscles counts (106 mm3 ) and platelets was related to parasite species and intensity of infection and also to total length and weight of host ( Clarias Iazera ) . The mean haematocrit value( Pcv%) in case of the infection with the cestodes Corallobothrium solidum was high ( 42.212), at low intensity of 1-4 worms per fish compared with non infected controls ( 33 i3) , however only in high intensity of infection with the nematode Contraceauml-30worom per fish high values were observed , in this study determined the condition factor to the total length and weight there were risk in the infection with both parasites . As for the Biochemical changes in case of C.s0lidum a significant increase was observed in serum globulin level ( 2.9 i 0.3)g/ ( (P>0.05) and total proteins ( 5i.05 ) compared with non infected controls( 2.8 & 3.4 ) respectively, however no significant effect on albumin level was observed . Moreover the investigation revealed acute effects on growth and wellbeing condition of host. There was a clear correlation of intensity of parasites with weight and total length of C. lazera . Electrophoresis of serum proteins from infected host showed a significant inecrease in the gamma, beta and alpha globulins , which indicates development of anemic, that was COI1flIIIl€d by the histopathology changes of liver . However in case of the nematode high infection was associated with increase in globulins , and decrease in albumin this was also observed with the cestode infection . However increase of albumin was observed in Contraceaum low and median infection and Corallobothrium solidum low infection infection. Serum proteins electrophoresis showed that hehninthic parasites afi'ect immuno globulins (IgM). Histopathological changes in the pyloric region of stomach showed that infection with the cestodes C. solidum and the nematode Contraceaum sp caused sloughing of mucosa and appearance of mast cells , haemorrages,and necrosis in the muscular-is mucosa . In the intestinal regions of C.lazera infection caused, hypertrophy of simple columnar cells , haemorrages , and sloughing of the mucosa and nerosis in the muscularis mucosa . Histopathological changes in liver in case of infection with the cestode Corallobothrium solidum revealed poor glycogen deposit , (devolping anemic) haemorrages , necrosis , infiltration with white blood cells with , dark stained excentric nuclei and opaque cytoplasm . However infection with Contraceaum revealed starvation ,vaculation , , and necrosis of hepatocytes with in the hepatpcytes infiltration of lymphocytes