Length- Weight Relationship and Condition Factor of Two Species of Tilapia and One Species of Mormyrops from a Tropical Dam in a Southwestern State, Nigeria

The length-weight relationship and condition factor of Tilapia zillii, Oreochromis niloticus and Mormyrops anguilloides from Itapaji dam, Ekiti State Nigeria were examined in this study. A total of 150 fish made up of 113 T. zillii (65 females and 48 males), 24 O. niloticus (11 females and 13 males) and 13 M. anguilloides (11 females and 2 males) procured directly from the fishermen were examined. The parameters „a‟ and „b‟ were determined from the linear regression of the logarithm of length and weight of the fish when transformed into the growth equation, W= aLb . The values of „b‟ for the fish species ranged from -1.16 to 10.12 and the result showed that the Cichlidae had negative allometric growth while Mormyrops showed positive allometric growth. The condition factor „K‟ value for female and male O. niloticus were closer to the recommended range of 2.9 to 4.8 while the „K‟ value of other two species were greater than 1 except in the female M. anguilloides. The difference in the „K‟ values may be caused by the variation in weight of individual fish species sampled as well as environmental factors to which they are exposed in the dam.

Keywords: Tilapia zillii, Oreochromis niloticus, Mormyrops anguilloides, Length-Weight relationship, Condition Factor.