||The goal of this study was to evaluate the suitability of marine fish viscera (MFV) as an alternative
protein in diet for juvenile Clarias gariepinus. Three isonitrogenous (43% crude protein) and isoenergetic
(gross energy 20 kJ.kg-1) diets were formulated to contain 0% (D0, control diet), 30% (D30) and 50%
(D50) of MFV, as fishmeal (FM) substitutes. The diets D0, D30 and D50 were compared with the
reference commercial diet Coppens® developed for African catfish. Fish (initial body weight: 8.0 ± 0.3g)
stocked at fifty-five per tank where fed at satiation in twelve (4 x 3 replicates) tanks for 42-day in a
recirculating water system. At the end of experiment, final weight (96.6 g - 111.0 g), daily weight gain
(2.1 g/day - 2.5 g/day), Specific Growth Rate (5.7%/day - 6.3%/day), feed conversion ratio (1.1-1.3),
protein efficiency ratio (1.8-2.2), yield (4.7 kg/m3 - 6.1 kg/m3) and annual production (41.1 Kg/m3/year -
53.1 Kg/m3/year) did not vary significantly until 30% MFV in diet (P > 0). Values in fish fed 50% MFV
were significantly lower (P ˂ 0). Cost-benefit analysis show a considerable reduction in cost of
production of one kilogram fish, to about 79.34% and 76.03% with fish fed 30% and 50% MFV,
respectively, compared to commercial diet. Thus, the MFV should be included up to 30% in diet for C.
gariepinus juvenile without negative influence on growth performance, feed utilization and production.
The results encourage more investigations in promoting of that environmental-friendly ingredient in the
production of C. gariepinus in Benin small-scale farms.