Prevalence and Characterization of Moulds Associated with Fish Feeds Sold in Kisii County, Kenya

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Date
2020Author
Nyamwaka, Irene Seila
Monda, Ethel
Ombori, Richard Omwoyo
Kwach, Johnson
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There 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 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 fungi.