The effects of brood stock size on the economy of catfish (<i> Clarias anguillaris</i>) fry production using the hormone induced natural breeding technique

Abstract

Eighty nine ripe female brooders of the catfish, Clarias anguillaris (Body weight. range: 150 1,200 g) were induced to spawn by hormone (Ovaprim^®) induced natural spawning technique over a period of 10 weeks. Matching ripe males were used for pairing the females at the ratio of two males to a female. Six ranges of brood stock body weight were considered as follows: <200, 200 - 399, 400 - 599, 600 - 799, 800 - 999, ≥ 1000 g and the number of fry produced by each female brooder was scored/recorded against the corresponding body weight range. The number of fry per unit quantity of hormone and the cost of producing a fry based on the current price of Ovaprim (hormone) were determined so as to ascertain the most economic size range. The best and most economic size range was between 400 599 g body weight with about 20,000 fry per ml of hormone and N0.028 per fry, while the females weighing 1000 g and above gave the poorest results of 9,519 fry per ml of hormone and N0.059 per fry. For optimum production of Clarias anguillaris fry and maximum return on investment, female brooders of body weights ranging between 400 599 g are recommended for hormone induced natural breeding exercises. (International exchange rate: N129.00/US$1.00 as at 01 April, 2006)

Keywords: Clarias anguillaris, brood stock size, induced breeding, fry production

Journal of Aquatic Sciences Vol. 21(1) 2006: 19-22