Aquaponics
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Publication Characterisation of Artisanal Catches in Selected Fishing Areas of The Lower Tana Delta and Malindi-Ungwana Bay, Kenya(Western Indian Ocean Journal of Marine Science, 2020-10-29) Dzoga Mumini; Simatele Danny; Munga CosmasShore-based assessment of fisheries resources in Ngomeni, Kipini and Ozi fishing areas of Malindi-Ungwana Bay and the Lower Tana Delta on the north coast of Kenya was conducted from January to December 2017 to establish catch composition, species richness, and fishing effort (catch-rate, number and types of fishing gears and crafts) in the marine, estuarine and riverine habitats. Distinct catch composition (R = 0.27, P < 0.05) was observed across the three habitats. Catch composition differed significantly spatially and seasonally across the three fishing areas, and between the north east (NE) and south east (SE) monsoon seasons (R = 0.332, P < 0.05). The wolf herring, Chirocentrus dorab, was the most abundant fish species in Ngomeni, centrally located in Malindi-Ungwana Bay, while the catfishes, Arius africanus and Clarias gariepinus, were the most abundant species in Kipini and Ozi, respectively. Gillnets operated from dhows (mashua) and fibre-reinforced plastic (FRP) boats in Ngomeni (marine), and canoes using-basket traps in Ozi (riverine), landed significantly larger Spanish mackerel, Scomberomorus commerson, and sea catfish, Arius africanus (Kruskal Wallis test: Df = 2; F = 197.141; p < 0.001; Df = 2, F = 490, p < 0.001), respectively. Species diversity by area in combination with habitat and type of fishing craft showed higher diversity for Ngomeni in the marine habitat with mashua fishing crafts than in Kipini. Significantly different catch rates (Df = 2, F = 10.43, p<0.001; Df = 1, F = 5.897, p < 0.021) were observed in the three (3) fishing areas and during the NE monsoon and the SE monsoon, respectively. Canoes were the most common fishing craft used, especially in Ngomeni, accounting for 37.1%, and 97.5% in Ozi, while mashua crafts accounted for 44.5% of the total fishing craft in Kipini. Monofilament nets were most common in Ngomeni (34.0%) while basket traps dominated the Ozi site at 63.6%. The Kipini area was dominated by handlines (28.8%). It is therefore evident that the three (3) fishing areas of the Malindi-Ungwana Bay and Lower Tana Delta showed significant differences in catch composition and size of fish caught, attributed partly to the variation in habitat types and fishing methods between the sites. Overall, the Ngomeni area was characterized by more advanced fishing craft with the majority powered by engines, including mashua and FRP boats, compared to Kipini and Ozi fishing areas where canoes were dominant.Publication Prevalence and Characterization of Moulds Associated with Fish Feeds Sold in Kisii County, Kenya(Journal of Advances in Microbiology, 2020-09-04) Irene Seila Nyamwaka, Ethel Monda, Richard Omwoyo Ombori and Johnson KwachThere is an increase in aquaculture in Kenya due to increased demand for fish as a source of white meat and increased population growth. Most fish farmers use plant-based ingredients such as peanuts, cottonseed, soybeans, maize bran and wheat as sources of protein for the fish feeds. These ingredients are very susceptible to attack by aflatoxigenic fungi. In humid climatic conditions like those found in Kisii County, growth of such fungi on fish feeds is accelerated due to absorption of moisture from the environment as a result of poor storage and sometimes improper drying. This study was conducted to determine the moulds associated with fish feeds sold in Kisii. Commercial fish feeds from five main outlets in Kisii County were sampled and analysed. Home-made fish feeds were obtained from three groups. Fungi were isolated using various media and percentage isolation _____________________________________________________________________________________________________ *Corresponding author: E-mail: ireneseila76@gmail.com; Nyamwaka et al.; JAMB, 20(8): 31-41, 2020; Article no.JAMB.60520 determined. The results show that fifteen fungal species were associated with fish feeds sold in Kisii County. They include Mucor spp, Penicillium glabrum, Fusarium oxysporium, Aspergillus oryzae, Aspergillus flavus, Aspergillus parasiticus, Alternaria spp, Penicillium citrinum, Stachybotrys spp, Cladosporium spp, Aureobasibium spp, Eurotium spp, Aspergillus versicolor, Aspergillus fumigatus and Aspergillus niger. The aflatoxigenic fungi comprising of A. flavus, A. parasiticus and A. niger were most prevalent in fish feeds obtained from Egetuki outlet (29 %) and least prevalent in Dombetty (16.6 %). The mean differences of fungal species were statistically significant (P<0.05) in four outlets. This shows that fish feeds sold in Kisii county are contaminated with aflatoxigenic fungiItem Sources of Fungal Contamination of Fresh and Dried Fish in Kisii County, Kenya(2020-12-31) Irene Seila Nyamwaka, Ethel Monda, Omwoyo Ombori and Johnson KwachAflatoxins are toxic secondary metabolites produced by Aspergillus flavus and Aspergillus parasiticus that frequently invade foods and feedstuffs. In humid climatic conditions like those found in Kisii County, growth of fungi on dried fish and fish feeds is accelerated due to absorption of moisture from the environment as a result of poor storage and sometimes improper drying. This can lead to creation of favourable conditions for the growth of the toxigenic fungi and consequently production of aflatoxins. This study was conducted to determine the main sources of fungal contamination of selected fresh and dried fish sold in Kisii county, Kenya. Samples of fish were randomly obtained from four main markets in the county. A structured questionnaire was used to determine the sources of fish, mode and hygiene of transportation, handling of fish, duration of storage, hygiene of packaging materials and display environment of fish. Levels of fish contamination were expressed in form of colony forming units per gram (CFU/g) of fish. One-way analysis of variance was used to determine mean differences in parameters analysed. The results revealed that CFU/g of fish from control samples were significantly less than those from fresh and dried fish samples from the various sources (p<0.05). There was generally no significant difference between CFU/g from both fresh and dried fish from the various sources. The study found out that fresh and dried fish sold in Kisii county are contaminated with fungi. There is therefore need for frequent surveillance on the sources of fish contamination and public sensitization of all those involved in fish supply chain. This will help reduce possible aflatoxin contamination thus promoting consumers’ healthy living.