Abstract:
Mozambique's aquaculture sector is in rapid development, although it faces constraints
inherent the gap between fish demand and supply due to high input costs. The use of
locally available feed materials can help reduce production costs. This research aimed to
evaluate the economic viability and zootechnical performance of Nilotic Tilapia juveniles
fed different levels of African Catfish fillet meal as a protein source. The study was
conducted at the ISPG fish unit in Lionde for 60 days, based on a DCC, with 4 treatments
(T1-0%, T2-50%, T3-75% and T4-100%) and 4 repetitions, making 16 experimental
units, populated with 25 juveniles each. A total of 400 animals with weight and initial
mean compliance of 58.12±7.06g and 102.05 ± 5.22mm, respectively, were used in the
study. Diets were balanced using Pearson's square method. The water quality parameters
evaluated were pH, dissolved oxygen, temperature and transparency, which were within
the optimum ranges for the cultivation of the species under study, except for the
temperature that presented minimum and maximum average values of 18.81±1.37 and
24.10±0.35ºC, respectively. The diets with the inclusion of flour from African catfish
residues, in the analyzed proportions (0, 50, 75, and 75%), presented a result of
zootechnical performance statistically similar to the control diet (P <0.05), but lower
economic result. The results indicate that the flour obtained from African Catfish fillet
residues can successfully replace fish flour at 50 and 75% without compromising the
productive performance of juveniles of Nilotic Tilapia. Total substitution (100%) shows
inferior performance, although, in statistical terms, it is similar to the remaining
treatments. Economically, FRB showed potential in reducing food costs, the higher the
FRB inclusion rate, the lower the production cost/kg was observed.
