Browsing by Author "Athanasio S., Mbonde"

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    Fish polyculture system integrated with vegetable farming improves yield and economic benefits of small-scale farmers.
    (Wiley, 2016-09-12) Samwel Mchele Limbu; Amon P., Shoko; Hieromin Amon, Lamtane; Mary Alphonce, Kishe-Machumu; Masanja Charles, Jorum; Athanasio S., Mbonde; Huruma Fredrick, Mgana; Yunus Daud, Mgaya
    This study explored the yield and economic benefits of African sharptooth catfish, Clarias gariepinus, and Nile tilapia, Oreochromis niloticus polyculture, reared in earthen ponds for 270 days integrated with Chinese cabbage, Brassica rapa chinensis, farmed for 45 days to small‐scale farmers in Tanzania. An integrated aquaculture–agriculture (IAA) system involving fishes and vegetables resulted in three and 2.5 times higher net yield than the culture of fishes alone and farming of non‐integrated vegetables respectively. Vegetables irrigated with pond water resulted in 1.8 times higher net and annual yields than those irrigated with stream water. The practice of fish–vegetable integration and growing of vegetables irrigated with pond water produced 14 and 13 times higher net annual yield, respectively, than the culture of fishes alone. The integrated system produced 20 and 150 times more net returns compared with vegetables irrigated with pond and stream water respectively. Integrating fishes with vegetables resulted in significantly higher annual net cash flow than the farming of fishes and vegetables separately. The study revealed that integrating fishes with B. rapa chinensis increases yields, income and food production to small‐scale farmers. Thus, small‐scale farmers can adopt IAA technology to meet the increasing demand of fish and vegetables, stabilize their incomes and diversify food production, consequently improving food security. These benefits will be realized by providing proper training in IAA technology and management skills to small‐scale farmers.
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    Phytoplankton and food selectivity in Nile tilapia reared in earthen ponds under monoculture and polyculture with African Sharptooth catfish.
    (Multidisciplinary Digital Publishing Institute (MDPI), 2017-06-16) Athanasio S., Mbonde; Samwel Mchele Limbu; Amon P., Shoko; Yunus D., Mgaya
    Phytoplankton availability is one of the most important biotic factors affecting the successful culture of Nile tilapia (Oreochromis niloticus, Linnaeus) in semi-intensive ponds. The present study investigated phytoplankton composition, abundance and food selectivity in Nile tilapia Oreochromis niloticus (Linnaeus, 1758) reared in monoculture and polyculture system with African sharptooth catfish Clarias gariepinus (Burchell 1822) in earthen ponds. Water samples and stomachs of 144 O. niloticus were collected from respective pond systems for examination of phytoplankton composition and abundance. The obtained phytoplankton species in water and stomachs were used to determine food selectivity of O. niloticus. The results showed significantly higher Chlorophyceae in polyculture than monoculture ponds. The gut contents of O. niloticus from both systems were mainly composed of Bacillariophyceae, Euglenophyceae and Cyanophyceae and detritus and insect remains. Bacillariophyceae, detritus and insect remains were selected as food by O. niloticus cultured in both systems. Findings from this study show that, under monoculture and polyculture pond systems, O. niloticus exhibit selective feeding consuming more Bacillariophyceae, detritus and insect remains.The results suggest that fish farmers can practice either monoculture or polyculture of O. niloticus without affecting its food selectivity.