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Economic performance of using Coppens (commercial fish feed) and locally formulated feeds for Clarias gariepinus culture was studied. Forty juveniles averaging a total length of 9.15 ± 0.17cm and weight of 20.00 ± 2.58g were used and fed twice daily at 3% of their body weight. The weight gain (WG), growth rate (GR) and specific growth rate (SGR) varied significantly (p<0.05), while mean growth rate (MGR) varied insignificantly between treatment groups (p>0.05). Water parameters were at the required level. Cost of experimental feed per kilogram was highest in Coppens (₦733.33 ($2.156853)/kg) but lowest for chicken offal based diet (COBD) (₦267.00 ($0.785294)/kg). Feed consumption was higher for Coppens group (41650.00g ± 315.34) but lowest for COBD group (38276.00g ± 432.97). Cost of feeding (FC) was lower for COBD group (₦ 10219.69 ($30.057912) ±115.60) but higher in shrimp based diet (SBD) group (₦ 30,543.19 ($89.832912) ± 231.25). The ICA was higher in fish fed Coppens (₦ 1933.33 ($5.686265) ± 0.00) but lower for COBD group (₦1467.00 ($4.314706) ± 0.00). The NPV was higher in fish fed Coppens (₦ 440998.26 ($1297.053706) ±11636.93), but lower in COBD group (₦ 132916.16 ($390.929882) ± 3297.24). The PI was highest in Coppens group (₦14.44 ($0.042471) ± 0.35) but lowest in COBD group (₦ 13.01 ($0.038265) ± 0.43). The GP was higher in Coppens group (₦439064.93 ($1291.367441) ± 11636.93) but lower in COBD group (₦131449.16 ($386.615176) ± 3297.24). The IC was higher in Coppens group (₦228.10 ($0.670882) ± 6.02) but lower in COBD group (₦90.61 ($0.266500) ± 2.25). The BCR was higher in fish fed coppens (1.78±0.04) but lowest in COBD group (0.71±0.01). Feed consumed, FC, ICA, NPV, PI, GP and IC varied significantly (p<0.05), while BCR varied insignificantly (p>0.05) between treatment group. The SBD and COBD were as effective as Coppens in terms of growth performance and economic benefits. More researches should be carried out on the use of locally formulated feeds in aquaculture.

The study on the reproductive indices and gonadal development of African catfish (Clarias gariepinus) fed shrimp based diet (SBD), chicken offal based diet (COBD) and coppens (commercial diet) was carried-out over a 22 weeks period in concrete tanks measuring 3.5 x 1.7 x 1.5 m3          (8.9 m3). Forty juveniles with average length of 9.15 ± 0.17 cm and weight of 20.00 ± 4.53 g were stored per group in triplicate, resulting in 360 juveniles in total. Fish were fed daily at 3% of their body weight through-out the duration of the experiment. The nutrient composition of the 3 nutrients differed significantly at p<0.05. The dissolved oxygen, temperature, pH and ammonia levels in the culture water with fish fed the 3 diets were within the required level for normal fish growth through-out the experiment. The gonadosomatic index (GSI) of the male C. gariepinus fed diet A (Coppens feed), diet B (SBD) and diet C (COBD) were 0.35 ± 0.03%, 0.41 ± 0.04% and 0.36 ± 0.02% respectively. Female C. gariepinus fed diet A, diet B and diet C had a mean GSI of 1.17 ± 0.26%, 0.88 ± 0.27% and 0.77 ± 0.06% respectively. The male gonad weight and GSI varied significantly between the treatment group fed coppens, shrimp based diet and chicken offal based diet (p<0.05), while female gonad weight and GSI did not vary significantly between treatment groups (p>0.05). The hepatosomatic index (HSI) of the male C. gariepinus fed diet A, diet B and diet C were 1.36 ± 0.07%, 1.18 ± 0.07% and 1.21 ± 0.06% respectively. Female C. gariepinus fed diet A, diet B and diet C had a mean HSI of 1.27 ± 0.09%, 1.20 ± 0.06% and 4.27 ± 0.38% respectively. The male and female HSI varied insignificantly between the treatment group at p>0.05. Fecundity was highest (3200 ± 717.90 eggs) in fish fed diet A, followed by fish fed diet B (2392 ± 749 eggs) and least in fish fed diet C (1973 ± 184 eggs). The mean fecundity varied significantly between the fish fed the 3 experimental diet at p<0.05. Normal arrangement of the oocytes, liver and testis was observed in fish fed COBD and SBD, just as in the case of the group fed coppens. Though coppens feed yielded better fecundity, the use of COBD and SBD is recommended for fish farmers in Nigeria. More researches should be carried out on using varying levels of chicken offals and shrimps in fish feed formulation.

A comparative study on the growth performance of African catfish (Clarias gariepinus) fed shrimp based diet (SBD), chicken offal based diet (COBD) and coppens feed was carried-out for 22 weeks in concrete tanks measuring 3.5 x 1.7 x 1.5 m3. Triplicate groups of 40 juveniles with average length of 9.15 ± 0.17cm and weight of 20.00 ± 2.58g were stored in each tank. A total of 360 juveniles were used throughout the study. Fish were fed daily at 3% of their body weight through-out the duration of the experiment. The nutrient composition of the 3 nutrients differed significantly at p<0.05. Weight gain (WG) (g) was highest (17189.33 ± 506.61g) in fish fed diet A (Coppens feed), followed by 15045.33±202.42 g (diet B) (SBD) and least (14357.33 ± 108.25 g) (diet C) (COBD). The Growth rate (GR) was highest in fish fed with diet A (111.62 ± 3.29 g/day), followed by 97.69±1.31 g/day (diet B), and least (93.23±0.70 g/day) in diet C. Specific growth rate (SGR) was highest in juveniles fed diet A (2.02 ± 0.02 %/day), followed by 1.94±0.01 %/day for diet B, and least (1.91±0.01 %/day) for diet C. Mean growth rate (MGR) was highest in juveniles fed diet A (11.88 ± 0.29 mg/day), followed by 11.74±0.15 mg/day for diet B, and least (11.69±0.09 mg/day) in fish fed diet C. The WG, GR and SGR varied significantly between the juvenile fish group fed the 3 diets at p<0.05, while MGR did not vary significantly between fish group fed the 3 diets at p>0.05. Fish fed diet A had a higher feed consumption (FC) (41650.00 ± 315.34 g/kg), than that fed diet B (39034.24 ± 86.34 g/kg) and then diet C (38276.00 ± 342.97 g/kg). Juveniles fed Coppens feed did better, with a feed conversion ratio (FCR) of 2.42 ± 0.06, followed by 2.59±0.04 for diet B and 2.67 ± 0.03 for fish fed diet C. Feed conversion efficiency (FCE) was higher in fish fed diet A (41.26±0.94 %), followed by 38.54 ± 0.54 % (diet B) and least (37.52 ± 0.51 %) (diet C). The FC and FCR varied significantly between the fish fed the 3 diets at p<0.05, while FCE was not significantly different between the 3 treatment groups at p>0.05. The water parameters of the culture water varied significantly between each treatment groups (p<0.05), and were within the rage suitable for normal growth of fish. Though coppens feed yielded better growth performance and feed utilisation, the use of COBD and SBD is recommended for fish farmers in Nigeria. More researches should be carried out on using chicken offals and shrimps in fish feed formulation.