%0 Journal Article %T Histopathological Effects of Gammalin 20 on African Catfish (Clarias gariepinus) %A Lawrence Ezemonye %A Temiotan Emmanuel Ogbomida %J Applied and Environmental Soil Science %D 2010 %I Hindawi Publishing Corporation %R 10.1155/2010/138019 %X Clarias gariepinus fingerlings exposed to lethal and sublethal concentrations of Gammalin 20 were investigated in a renewal static bioassay with particular reference to behaviour, survival, and histopathological changes. Early symptoms of gammalin 20 lethal poisoning were, respiratory distress, increased physical activity, convulsions, erratic swimming, loss of equilibrium, and increased breathing activity. Behavioural response was dose dependent and decreased with decreased concentration. The 96-hour lethal concentration (LC50) value was 30£¿ppb. Histopathological changes of the gill, liver, and intestinal tissues of fish treated with sublethal concentration of gammalin 20 for twelve weeks showed gill distortion and fusion of adjacent secondary lamella as a result of hyperplasia and excessive mucus accumulation. The liver showed swelling of hepatocytes with mild necrosis, pyknosis, and vacuolation, while the intestine showed yellow bodies of the lamina propria at the tip of the mucosal fold. 1. Introduction Environmental factors of both natural and anthropogenic origins have been known to induce alteration of different magnitudes in the physiological and biochemical status of animals [1, 2]. Therefore, biomarker parameter assessment is a means of environmental monitoring, with the advantage of providing quantitative response as valuable information on ecological relevance as well as on the acute/chronic adverse effects caused by water pollution [3]. Alteration in the chemical composition of a natural aquatic environment, due to contact with hazardous substances like heavy metals, pesticides, and effluents from industries usually affect the behaviours, biochemistry, and physiology of the fauna including fish [4]. Water is one of the most precious natural resources on earth, and it creates a wide range of benefits to humans, including fisheries, wildlife, agriculture, urban, industrial, and social development [5]. However, the unregulated release of agricultural chemicals especially pesticides into water bodies have caused environmental problems to all classes of organisms in the aquatic habitat. The aquatic ecosystem is faced with the threat of biodiversity loss due to indiscriminate use of pesticides [6]. Gammalin 20 is a widely used organochlorine pesticide employed in veterinary and human medicine to treat ectoparasites and pediculosis. It is also used in the control of a broad spectrum of phytophagous and soil-inhabiting insects, public health pests, and animal ectoparasites. It is used in fishing industries for fish kill and on a wide range of crops %U http://www.hindawi.com/journals/aess/2010/138019/