Mycotoxin prevalence in stored animal feeds and ingredients in Rwanda

Aflatoxins and fumonisins are fungi metabolites produced when climate conditions are favorable. They contaminate feed ingredients when storage conditions are unfavorable. Aflatoxins and fumonisins have a negative impact on animal health and productivity. Humans are indirectly exposed to mycotoxins when they consume contaminated animal source foods from livestock fed contaminated feeds. A total of 3328 feed samples were collected in all 30 district of Rwanda between March and October 2017. Four categories of participants participated in the study (dairy farmers, poultry farmers, feed processors/grain millers, and feed vendors). Feed samples were highly contaminated with aflatoxins but not fumonisins. Average aflatoxin levels were highest in dairy feeds (108.3 µg/kg) followed by poultry feed (103.81 µg/kg). Average aflatoxin levels were lowest in samples from feed vendors (88.64 µg/kg) compared to samples from feed processors (94.95 µg/kg). This study documents high levels of aflatoxin contamination in feed samples, and recommends year-round surveillance of feed ingredients and mixed feeds for mycotoxin presence. Additionally, more awareness through communication and education needs to be raised among stakeholders in the evolving feed value chain in Rwanda to mitigate the consequences of mycotoxin contamination on public health and animal produtivity.