Influence of tropical seasonal changes on oocyte diameter, responses to hormonal induction and hatching quality in two strains of the catfish, Heterobranchus longifilis Val. (Clariidae) |
| |
Authors: | David Nguenga Guy G Teugels Marc Legendre & Frans Ollevier |
| |
Institution: | Institute of Agricultural Research for Development (IRAD), Fishculture &Fisheries Research Unit, Foumban, Cameroon; Musée Royal de l'Afrique Centrale, Laboratoire d'Ichtyologie, Tervuren, Belgique; Katholieke Universiteit Leuven, Laboratory of Ecology &Aquaculture, Leuven, Belgium; IRD/GAMET (UR 081), Montpellier Cédex 1, France |
| |
Abstract: | A comparison was made between the oocyte diameter, pseudo‐absolute fecundity (PAF) and egg quality of two strains of the catfish, Heterobranchus longifilis, maintained in outdoor ponds under a tropical highland climate in Cameroon. The results indicated that circannual endogenous rhythms for ovarian recrudescence and regression are absent in H. longifilis, irrespective of breeding history, age and strain. There appeared to be a possible slight adverse effect of climate (dry season) on reproductive performance of both strains. Oocyte diameter and PAF increased with increasing fish weight when data from both strains were combined, indicating that the two strains may exhibit the same reproductive performance. Viable eggs were obtained all year round after hormonal induction. It is concluded that for propagation of H. longifilis in tropical African countries, broodfish could be maintained in outdoor earthen fish ponds with proper feeding. |
| |
Keywords: | Heterobranchus longifilis Clariidae strain comparison reproductive performance tropical highlands climate Cameroon |
|
|