Morphometric and Meristic Characteristics of Clarias gariepinus from Controlled and Uncontrolled Population from Southwestern Nigeria

摘要

Studies on the nineteen morphological characteristics and meristic traits of C. gariepinus collected from those bred by a fish farmer in a fish pond in Emure- Ekiti (controlled population) and those from the wild population in Ogbese river (uncontrolled population), in Ado-Ekiti, Ekiti State Nigeria were carried out between August and December, 2012. One hundred and twenty –three (123) fish individuals collected by cast and dragging nets were bought, out of which sixty-one (61) were from the fish farm in Emure- Ekiti and sixty-two were from Ogbese river. The mean body weight and total length of the fish were 530.67±18.74g and 42.53±0.55cm and 507.02±26.26g; and 42.40±0.58cm for the controlled and uncontrolled fish population respectively. The length-weight relationship values were logW = -0.9961 +2.2781logL and logW = -1.3230 +2.4661logL for controlled and uncontrolled C. gariepinus population respectively. The results recorded on the mean body weights (530±18.74 and 507±0.02) and mean lengths (42.53±0.55 and 42.40±.0.58) of the fish from the two populations are not statistically different. But there are variations between and among the two fish populations. The condition factor (K) values are 0.69±0.02 and 0.67±0.01 for the controlled and uncontrolled fish population. The condition factor values which were not significantly different from each other showed that the fish from the two populations are not well fed. The robustness of the fish from uncontrolled population may be as result of enough fertility of the river or that there was a lesser competition from other fish species for the available food resources. There is need to determine the factor(s) which favours the growth and development of the fish from Ogbese river (uncontrolled population).