Length-weight relationship and condition factor of Clariid fish species in Kano Rivers, Kano State, Nigeria
Fish found in natural tropical and sub-tropical water system experience frequent growth fluctuations. The study was conducted to determine the length-weight relationship and condition factor of Clariid species (Clarias gariepinus, Heterobranchus longifilis and Synodontis clarias) in Kano state of Nigeria. About 177 fish samples were collected from six rivers (Thomas, Ghari, Tiga, Duddurun-Gaya, Karaye and Bagwai) across the length and breadth of Kano state. Body weight (BW=248.48g), total length (TL=32.74cm) and standard length (SL=26.16cm) were determined. The length-weight relationship and condition factors were also determined. The condition factors showed varying degree of well-being of fish sampled from their habitat, and ranged from K = 0.37 to 0.89. The equation for the lengthweight relationship for the three strains is: C. gariepinus = -329.86+17.56TL, H. longifilis = -241.49+14.28TL and C. clarias = -428.51+22.72TL. Body weight and length had positive and significant relationship (r = 0.73 TL; r = 0.75 SL).
Keywords: Length-weight relationship, condition factor (Ponderal index), Clariid species