Aflatoxin contamination status in selected animal feeds and concentrates sold in feed stores in Kampala, Uganda

Abstract

This study was conducted to evaluate the status of aflatoxin contamination in commercial animal feeds and concentrates sold in feed stores in Kampala, Uganda. Aflatoxins are toxic metabolites produced by Aspergillus species, known to reduce animal productivity and pose public health risks through residues in milk, meat, and eggs. Despite existing regulatory limits, there has been limited systematic surveillance of commercial feeds in Kampala, where most livestock farmers source their feeds. A cross-sectional analytical design was employed, and 60 feed samples were collected across five divisions of Kampala, representing four feed categories (layers mash, dairy meal, pig concentrate, and fish feed). Thin Layer Chromatography (TLC) was used to detect aflatoxins. Findings showed that 48.3% of samples tested positive for aflatoxins. Among the contaminated samples, 70% contained aflatoxin G, while 30% contained aflatoxin B. Layers mash recorded the highest contamination (66.7%), followed by dairy meal (53.3%), fish feeds (46.7%), and pig concentrate (33.3%). Contamination levels also varied by manufacturing period, with prevalence rates of 35%, 45%, and 80% in May, June, and July, respectively. These findings indicate that aflatoxin contamination is widespread in Kampala’s feed stores and influenced by both feed type and season of manufacture. The high levels observed, particularly in poultry and dairy feeds during wetter months, raise concerns about food safety and livestock productivity. Furthermore, according to the Uganda National Bureau of Standards (UNBS, 2018), the maximum permissible level of aflatoxins in animal feeds is 10 µg/kg; however, there is limited data on the extent to which feeds on the Ugandan market comply with this standard. The study concludes that aflatoxin contamination poses a significant threat to the livestock sector and recommends nationwide surveillance and quantitative assessments to strengthen evidence for policy and interventions.