Mycoflora, aflatoxin, and fumonisin levels present in layer feed in Nairobi County

Abstract

Layer feeds in Africa largely comprise cereals that are susceptible to mycotoxin contamination. Mycotoxins pose a health and production hazard in the poultry industry. This study investigated the mycoflora associated with layer feeds and mycotoxin content. 50 samples each of chick mash, grower mash, and layer mash were sampled from five regions in Nairobi County where urban poultry farming is carried out. Dilution plate technique was used to isolate fungi in Potato Dextrose Agar (PDA) and identified using morphological and molecular methods. Total aflatoxins (AF) and total fumonisins (FUM) levels were screened using Enzyme- Linked Immunosorbent Assay (ELISA). Aspergillus (91%), Penicillium (77%), Fusarium (13%), Mucor (11%), Rhizopus (9%), Cladosporium (4%), and Cochliobolus (1%) were isolated. AF was detected in 65% of feed samples (0.22 μg/kg - 157.89 μg/kg) while FUM in 91% of feed samples (210 μg/kg - 15173 μg/kg). Sixty-two samples (42%) had AF levels greater than the Kenya Bureau of Standards (KEBS) recommended limit of 10 μg/kg in poultry feed. No sample contained FUM levels higher than the European Union (EU) recommended limit of 20000 μg/kg. Our results highlight AF contamination in farms in the County, raising concern to poultry and public health due to AF residues in eggs.