Storage Period; its Effect on Efficacy of Non-piscine (Frog)Hormone used in Inducing Ovulation in African Catfish ( Clarias gariepinus Burchell, 1822)

摘要

The study examined the effect of varying storage period on the efficacy of frog pituitary with the aim of determining the optimum period required for effectively enhancing induction ovulalation, maturation and artificial propagation of Clarias gariepinus . Acetones dried pituitary extract obtained from non piscine source, the African bullfrog ( Rana adspersa , were stored over a period of 16 weeks and used to induce spawning in the female Clarias gariepinus ). Fresh pituitary extract was used as control having being previously worked upon and confirmed to be effective. There were significant differences in percentage fertilization of the eggs with the fresh hormone giving the highest yield and the hormone stored for 3 and 4 months giving least. The hormone stored for 4 weeks gave relatively high percentage fertilization and can therefore be used as optimum storage period.