Comparative Study of Carp Pituitary Extracts (CPE) and Ovupin-L on Induced Breeding in African Catfish (Clarias gariepinus)

Abstract

A comparative study of Carp Pituitary Extract (CPE) and Ovupin-L on induced breeding of African catfish (Clarias gariepinus) was conducted in applied hydrobiology and fisheries unit of Zoology Department, University of Jos. 24 brood stocks (12 males and 12 females) were sourced and selected from a private fish farm at Gangare, behind Murtala house Jos between the months of July to August 2010. Four of the females were hypophysized with 3mg, 4mg, 5mg and 6mg/kg body weight (BW) respectively of carp pituitary extract; four were hypophysized with 0.3, 0.4, 0.5, and 0.6mg/kg (BW) ovupin-L while the remaining four were injected with 0.3, 0.4, 0.5, and 0.6ml/kg (BW) of normal saline which serve as a control. The females were isolated separately and kept in plastic tanks (A-L) for latency period of 14hrs after hypophysation, while the males were kept in a single plastic tank. And were later dissected and testis removed to obtain milt which was used to fertilize the stripped eggs. The number of eggs spawned was estimated using standard formula. The result revealed that, all the females hypophysized with CPE and ovupin-L spawned in all the dosages but no fish spawned in all the dosages of normal saline. Ovupin-L at 0.5 ml/kg gave the best result in all the four parameters of fecundity investigated. There was a significant difference between the CPE and ovupin-L on fecundity and fertilization of Clarias gariepinus with ovupin-L performing better than CPE in all the parameters (p <0.05). Ovupin-L at dosage of 0.5ml/kg highly significant than other tested parameters in Clarias gariepinus, the dosage with the lowest output was obtained with CPE at 0.4mg/kg body weight.

Keywords: carp pituitary, extract, ovupin-L, African catfish, induced breeding, hypophysation.