水産養殖研究開発ジャーナル

概要

Evaluation of Productivity and Profitability of Nile Tilapia (O. niloticus) with Beetroot (Beta vulgaris) and Carrot (Daucus carota)

Teklay Gebru

Integrated fish farming system with vegetables using poultry manure as a fertilizer can play an important role in increasing food production, income generation, employment opportunities and waste removal. Thus, the main objective of this study was to evaluate the productivity and profitability of fish-vegetable (beetroot and carrot) integrated aquaculture system. The experiment was conducted from December 2020 to March 2021 in Hawassa University, Ethiopia. For this experiment, one pond with a size of 10 m × 15 m × 1.7 m for fish stocking and 114 m² lands for vegetable growth was used. In this pond 200 fingerlings of Nile tilapia (O. niloticus) were stocked at a stocking density of 1.3 fish/m² with average weight of 7.84 g. The pond was fertilized with 0.1 kg/m²/week of poultry manure. In addition to this, the fish was given a supplementary feed. For vegetable growth 24 plots of 2 m × 2 m were prepared and two vegetables namely, beetroot (Beta vulgaris), and carrot (Daucus carota) were planted in three replications of four treatments, i.e., plants treated only with pond water (T1), fertilizer (DAP and Urea) and tap water (T2), manure and tap water (T3) and as a control tap water only (T4). The experimental design for vegetable production was 2 × 4 factorial designs. The average final weight of the fish was 61.76 g and total production of fish was 12,352 g. The results revealed that the edible parts of beetroot and carrot productions were 12.9, 14, 11.8 and 5 kg/plot and 3.8,6.2,3.5 and 2.6 kg/plot in T1, T2, T3 and T4, respectively. Results of the general linear model revealed that beetroot productions of T1 were significantly different (p˂0.05) from T4 but not from (p˃0.05) T2 and T3 while, for carrot production T1 was different from (p˂0.05) T2 and T4 but not from T3. Based on the yield obtained beetroot production was more profitable than carrot production. Cost benefit analysis of the system revealed that net returns of the integrated aquaculture system were higher than unitary farming practices. Depending on the current study fish farmers could improve yields and net profits by using beetroot as vegetable component in integrated fish farming system.