To obtain a reliable and appropriate method for mass propagation of A. occidentalis (Valenciennes, 1840) fingerlings, different experimental trials on the artificial propagation and larval rearing will be investigated in Zambia over a 16-week period from Nov. 2021 – Mar. 2022. The experimental trials will be conducted to induce spawning using natural pituitaries from either the common carp, catfish, and/or tilapias or synthetic hormones (Ovaprim, HCG & LHRH-a). The main objective of the study will be to develop a methodology for the artificial propagation of the giraffe catfish for aquaculture development and stock enhancement in Zambian freshwater systems. This will be done by designing breeding protocols for: 1) collecting and transportation of live fish; 2) spawning of broodfish; 3) appropriate hormone and dosage inducing spawning; and 4) for the rearing of larval and nursing into fingerlings. Mitigation measures to increase productivity of the giraffe catfish larvae will be suggested. The analysis is expected to reveal as to whether the undertaking is labour intensive, technically reliable and economically feasible for an aquaculture business rearing the giraffe catfish.
In Zambia, the giraffe catfish (Auchenoglanis occidentalis) has commercial importance found endemically in Lakes Tanganyika, Mweru-Luapula and the Bangweulu Complex.
Despite its commercial importance, limited research has been conducted on its reproductive biology, feeding behavioral patterns, nutritional requirements, and natural/artificial propagation making it a priority area of aquaculture research (DoF, 2019, unpublished; Musumali et al, 2009).
To address the problem of insufficient fingerlings obtained through natural propagation, a 16-week experimental trial will be conducted in an effort to develop a methodology for the artificial propagation of the giraffe catfish in captivity to foster aquaculture development and sustainable stock enhancement in concrete tanks and earthen ponds. Fresh water will be circulated in the concrete tanks and ponds. Female broodstock of the giraffe catfish will be subjected to induced breeding experimental trials through three trials (adapted from de Graaf, 1995; Woynarovich & Horvath, 1980): 1) LHRH-a, 2) Ovaprim, and 3) HCG hormones for a minimum of 10 female broodstock.
Observations will be made as to whether spawning would have occurred for a period of 5 days after subjecting them to different hormonal doses. Further observations as to the mortality rate will be observed and other morphological features assessed. Results obtained will be subjected to statistical tests for significant differences.
Expected outcomes include: adapting the collection and transportation protocol; an appropriate hormone and dosage capable of inducing spawning; and a protocol for rearing of larval and nursing of giraffe catfish.
This analysis should reveal the viability of artificially propagating the giraffe catfish (A. occidentalis), the labour orientation, technical reliability and economic feasibility of undertaking an aquaculture business rearing the giraffe catfish.