Unité de recherche en Biodiversité et Exploitation durable des Zones Humides(BEZHU), Facultés des Sciences Agronomiques, Université de Lubumbashi, Haut-Katanga, R.D. Congo, RD Congo
Improvement of the agricultural production as well vegetable as animal remains the single solution to fight against malnutrition. This study was initiated in the objective to evaluate the performances of growth between Clarias gariepinus and Clarias ngamensis and their hybrids. The test was carried out during seven days to the zoological garden of Lubumbashi. The eggs of the females of each species were mixed then separate in 2 batches of which one is fertilized by the two males of the same species and the other by the two males of the other species. After fecundation, the eggs were incubated in 9 plastic basins in completely randomized device: 3 for C. gariepinus, 3 for C. ngamensis and 3 for the hybrids with 3 repetitions. At the resorption (three days post blossoming), the larvae were divided into 9 batches of the 120 larvae each one. The results obtained show that C. ngamensis presents a weaker performance on all the parameters evaluated except for the relationship between the weight of the laying and the live weight of parent. While C.. gariepinus and the hybrids presented performances very high this last specie would be advisable to the farmers of Lubumbashi to improve their production.
This work was initiated in the objective to characterize and identify the species of the Clarias kind within wild stock as servant in the zoological garden of Lubumbashi, RDC. For the identification groups, the techniques of measurement and counting were carried out on the basis of 7 morphometric measurement on 70 fish, in addition to the counting of the branchiospines on the first branchial arc and of the vertebrae. The study was supplemented by the morphological observations on the presence of the outline of the fat fin. The results obtained indicate that there are two species, C. gariepinus and C. ngamensis. Indeed, the morphological observations supported by the analysis of the neurales spines indicate that there are individuals presenting the atrophied fat fin (C. ngamensis) and of other not (C. gariepinus).The number of the branchiospines on the first arc branchial also states that certain individuals lay out about it in a high number than others. Clarias gariepinus presented more of the branchiospines on the first arc than Clarias ngamensis. These results show obviously that in the batch of fish raised at the zoological garden of Lubumbashi, there are two species of the Clarias kind.