The study on the characteristics of growth and condition factor K of Clarias jaensis was made in the floodplain of Mbô in Cameroon according to site, season, sex and size class. To assess the structure and dynamics of the population of C. Jaensis, in order to reduce mismanagement of fishing, 230 fish caught by "hawk" type gill nets, hooks and baited traps were collected monthly in three sites (Menoua, Nkam and flooded ponds) among fishermen between November 2016 and September 2017. The measurements and weighings of the total and standard lengths, then the total weight and eviscerated weight of the specimens ranged from 12.00 to 52.00 cm and 10.50 to 47, 50 cm respectively; Between 9.99 to 1165.59 g and 8.65 to 1119, 80 g. Overall, this species has a positive allometry growth. However, it showed seasonal variations. Thus, in the dry season, it passes from positive allometry to negative allometry regardless of sex and state of maturity, then isometry growth in the Nkam River to allometry positive in Menoua and flooded ponds. Condition factor K varied between 1.05 and 1.17 regardless of the factor considered. However no significant differences were observed. In view of these results, C. Jaensis could be considered as potential candidate for aquaculture
A zooplankton production trial based on chicken manure and guinea pig droppings was conducted between July and August 2014 at the Dschang University Research and Application Farm to contribute to the improvement of the productivity of fish farming systems. This work was aimed at determining the period and the best fertilizer to produce some zooplankton of interest necessary for larval rearing. An experimental design of 2 treatments and one control (unfertilized): T1 (chicken manure), T2 (guinea pig droppings) at a rate of 2.13 kg /are each triplicate was used in a completely Randomized 9 basins of 1 m3 previously inoculated with copepods and rotifers at densities of 14 and 45 ind / l of water respectively. Physico-chemical parameters of water and biological (zooplankton) follow-up was done every 2 days and the collected data were submitted to a one-way analysis of variance. It follows that: Except for temperature, pH and water depth, fertilizers had a significant effect on the physico-chemical characteristics of the water (p < 0.05). The most significantly high zooplankton densities (1161 ± 15 ind / l) (p <0.05) as well as rotifer and copepod species were obtained on day 12 and day 20 in basins fertilized with chicken manure, on the 14th and 22nd day for those fertilized with Guinea pig’s droppings. The highest densities, biomass, daily production and intrinsic growth rates of the copepods were observed in basins fertilized with guinea pig droppings. Each of the fertilizers has been shown to be of interest to produce a specific type of zooplankton, guinea pig droppings for copepods and chicken manure for rotifers.