-Short Communication COMMUNITY OF HELMINTH PARASITES IN RITA RITA (HAMILTON BUCHANUN)

Abstract

Key words: Rita rita, helminthes, prevalence and intensity of parasites. A majority of fishes carry heavy infection of parasites, which cause deterioration in the food value of fish and may even result in their mortality. Besides, there are a number of ‘helminth parasites ’ which are transmitted to men only through fish. The activities of parasite damage the tissues lining the wall of intestine, stomach, bile duct, liver, etc and cause microscopic lesions in the host’s tissue which become the site for secondary infection by bacteria. Wisneiwski (1958) stated that the character of a water body influences and determines the parasite fauna of its community. The physiological and biological features of the host affect the community of parasites even more seriously (Bibby 1972), and these factors determine the final composition of parasite fauna of the fish. Little is known about the distribution, pathogenic effects and control of most of the diseases in natural population of fresh water fish. The helminth parasite fauna of fresh water fishes, its frequency and distribution have been studied in many parts of the world (Kennedy and Hine 1969). The helminth parasites of fishes may herm their hosts in variety of ways e.g. a) by causing mechanical injury and atrophy of blood vessels or other ducts, b) by introducing toxic metabolic by products able to produce changes in the blood, enzyme, vitamin and hormone activity of the host, c) by depriving the fish from its nutrition, d) by acting as carrier or vectors of other pathogens and e) by providing a point of category for other pathogens through mechanical damage (Mehra 1991). The fauna of trematodes, nematodes and cestodes, mainly caryophyllides are found both in marine and freshwater fishes of Bangladesh, as the temperature never falls below 4°C, which is a suitable temperature for excellent survival and distribution of these parasites. Bashirullah (1973), Ahmed (1981), Zaman et al