Metazoan Parasites Research Paper

Diseases caused by Metazoan Parasites Metazoan parasites are multicellular, macro in size with complex organs, direct or indirect life cycle, and evolved to have specialized morpho-adaptation for parasitism. Metazoans include a diverse group of parasites, viz., myxozoans, helminths (monogeneans, digeneans, cestodes, nematodes and acanthocephalans), crustaceans (copepods and branchiurans) and hirudineans.
Myxozoans
Myxozoans are coelozoic and histozoic metazoan parasites with microscopic body size and structure. They are the most important group of parasites infecting vital organs like gills, brain, heart and skeletal system and causing heavy losses of juveniles. Several species of these pathogens have been reported from various parts of
catla was described by Kumar et al. (1986). Dey et al. (1988) also reported mass mortality of C. catla due to Myxobolus infection. Seenappa and Devaraj (1990) described Myxobolus infection in fry and fingerlings of C. catla from Karnataka. Ramakrishna (2005) recorded seven myxosporean parasites from the gills, fins, and scales of C. catla and L. rohita in fish ponds of Kolleru area of Andhra Pradesh. He observed severe infection of myxosporeans in fish less than 250 g in weight, especially during the winter season, when the ambient temperature was low. Hemananda et al. (2006) recorded pathogenicity and mortality due to Myxobolus haldi infection in the gill filaments of C. mrigala. Histopathological changes caused by M. haldi in all the three Indian major carps have been described (mention something as this would otherwise be taken as a vague observation). The presence of Myxobolus cysts in the highly hypertrophied primary lamellar tips with inflammatory reactions at the site of cyst formation and necrosis of renal tubular epithelium,
Although there are several reports on the occurrence of Hennegua infection from different parts of the country, fish mortality owing its infection has so far never been reported in the literature (Haldar et al. 1983; Haldar and Mukherjee 1985; Kalavati and Narasimhamurti 1985; Haldar et al. 1997; Hemananda et al. 2008). Maheswari (1986) documented protozoan Myxosoma cerebralis on C. mrigala causing whirling disease with the affected fishes showing typical signs of deformed spinal cord as in the case of