Influence of Fertilizer Type on Zooplankton Production, Survival Rate and Growth Characteristics in Sub Adults Papyrocranus afer in Ponds

Cameroon’s coasts are vulnerable to the effects of coastal erosion and climate change, thus affecting fishing through reduced catches and destruction of habitats. Reducing these risks requires mobilizing several sectors, notably aquaculture through the domestication of endogenous species. In order to evaluate the nutrition of Papyrocranus afer juveniles their captivity, a diet based on zooplankton production was carried out. This study took place at the Laboratory of Aquaculture and Demography of Fisheries Resources of the Institute of Fisheries Sciences from May to June 2023. 54 juveniles of Papyrocranus afer with an average length of 31.92 ± 2.30 cm and an average weight of 173.20 ± 1.20 g was used and divided in to treatments: T0 (Papyrocranus afer + Coppens), T1 (Chicken droppings without Papyrocranus afer), T2 (chicken droppings + Papyrocranus afer), T3 (pig manure without Papyrocranus afer) and T4 (pig manure + Papyrocranus afer). Zooplankton sampling was carried out as well as survival and growth. The results show that water temperature and transparency were higher at T0 (27.41 ± 0.50°c, 7.40 ± 0.23 and 60.10 ± 3.59 cm), ammoniac, nitrites and nitrates were elevated at T3 (6.93 ± 015, 7.97 ± 0.08 and 40.58 ± 0.10) mg/l. Zooplankton density was high at T3 (2,268 ind/l) and low at T0 (746 ind/l). SR, WG, DAG and SRG were significantly elevated at T4 (100%, 255.68 ± 0.8 g, 1.25 ± 0.01 g/d and 0.73 ± 0.52% g/day). It appears that Papyrocranus afer can be bred in captivity, providing a sustainable solution to the conservation of this endangered species.

Keywords: Influence, fertilizers, zooplankton, survival, growth, Papyrocranus afer, captivity.