eng Science and Education Publishing Applied Ecology and Environmental Sciences 2013-05-30 1 1 37 40 10.12691/aees-1-3-3 AEES2013133 article O.A. Akinrotimi ojoakinrotimi@yahoo.com 1 U.U Gabriel 2 O.O. Orokotan 3 African Regional Aquaculture Centres/Nigerian Institute for Oceanography and Marine Research. Port Harcourt, Rivers State, Nigeria Department of Fisheries and Aquatic Environment, Faculty of Agriculture, Rivers State University of Science and Technology, Port Harcourt, Rivers State, Nigeria Gabrovic Agri Nig. Ltd. Fishery Consultancy Services,, Eliozu Junction, Rumuodara, Port Harcourt, Rivers State Nigeria The effect of anaesthetic metomidate on the enzymes activities (Alanine transminase ¨C ALT; Aspartate transaminase ¨C AST; Alkaline phosphatase-ALP and Lactate dehydrogenase ¨C LDH) in female Clarias gariepinus was investigated using different concentrations (0.00mlL^-1 ¨C control; 0.25; 0.75; 1.00; 2.00; 6.00; 8.00; 10.00 and 12.00mlL^-1) in triplicates. The results from the study indicated that the anaesthetic caused a concentration dependent significant increase (p < 0.05) in the four enzymes under consideration. The highest activities in all the enzymes were observed in 12.00mlL^-1 and the lowest in the control. The results from this work therefore suggests that the anaesthetics impair enzymes activities in the fish which was more noticeable in the fish exposed to higher concentration of 8.00-12.00m/L^-1. Hence caution should be exercised in the application of this anaesthetics in sedation of C. gariepinus. http://pubs.sciepub.com/aees/1/3/3/aees-1-3-3.pdf anaesthetics aquaculture stress catfish enzymes