Identification, distribution and prevalence of ecto-parasites associated with cultured fish in Ogun State, Nigeria

Public health issues can he considered as those of direct importance to both producers and consumers of fish and include broader issues of food production, processing and delivery systems. As aquaculture assumes an expanding role in meeting consumer demands for fish and fishery products, it is natural that they meet safety and quality standards. Aquaculture is a growing industry in Nigeria and it has assumed commercial importance activity. This study was part of the project on epizootiological survey of pathogenic diseases of cultured fish species and is aimed at identifying ecto-parasite associated with cultured fish in Ogun State, Nigeria. The study which was carried out in 2012 covered fifty fish farm, spread across the three senatorial zones. Five pieces of fish were randomly picked from each farm surveyed. Participants observation and structured questionnaires were administered to fish farmers in order to gather information on source of fries, fish feeding and feed type, use of manure and its type, pond type, stocking density, pond hygiene, water source, frequency of changing water and history of diseases and mortalities of fish. Before the fish samples were collected, pond size and physicochemical water quality were assessed. Water test kits were used to measure parameters like iron, nitrate, alkalinity and ammonia. All the procedures for physicochemical water quality parameter analysis was done according to the manufacturer's instructions. Water pH was measured using a probe while dissolved oxygen and both water as well as air temperature were measured by using Hanna kit. All types of farms are included in the survey such as hatcheries, brood stock farms as well as grow out farms. The study revealed the spread of parasites across the senatorial zones. The most common encountered parasites were Trichodina sp, Gyrodactylus sp, Dactylogyrus sp and trematodes. The intensity of the parasites differed markedly