Veterinary drug use in poultry farms and determination of antimicrobial drug residues in commercial eggs and slaughtered chicken in Kaduna State, Nigeria

The occurrence of veterinary drug residues in poultry products in Kaduna state was determined. Information on drug use was obtained from ten layer flocks weekly for 10 weeks. Two hundred commercial eggs, and 378 slaughtered chicken faeces were examined for antibacterial drug residues using a disc diffusion microbial inhibition test with Bacillus cereus ATCC 11778, and Micrococcus luteus ATCC 9341 respectively. All 10 farms used a drug at least once, nine used antibacterial drugs for either prophylaxis, therapy or both. None of the farms observed drug withdrawal period. Two eggs (1%) and 82 (21.8%) of the chicken faeces were positive. Broilers had a significantly higher incidence (33.1%) for antibacterial substances at slaughter (χ2,P<0.01) than layers (23.6%) and local chicken (4.8%).