Assessment of veterinary drug use and determination of antimicrobial residues in broiler chicken meat in Urban district, Zanzibar, Tanzania

Abstract

A cross-sectional study was conducted between October 2009 and January 2010 to assess veterinary drug usage by broiler chicken farmers and to determine antimicrobial residues in broiler meat in Urban district, Zanzibar, Tanzania. Fifty five smallholder farmers were interviewed on types of  antimicrobials, reasons for use, their awareness on antimicrobial withdrawal periods and effects of antimicrobial residues in humans. Interviews with  key informants were used to supplement the information from farmers. Up to 66% of the respondents were aware of drug withdrawal periods, however, only 45.5% reported to comply in fear of losses and limited awareness of health effect associated with antibiotic residues. Key informants reported that there was no inspection of chicken meat for residues and the  indiscriminate use of veterinary drugs was fueled by trade liberalization. To determine antibiotic residues, 72 broiler meat samples were analysed by agar well diffusion and Delvo tests. Laboratory results indicated that 76.4% of the broiler meat samples contained antimicrobial residues. High proportion of positive samples in this study suggests that there is high risk of public exposure to antimicrobial residues through consumption of chicken meat in Urban district. Poultry farmers should be educated on the importance of drug withdrawal periods and the possible human health  effects associated with consumption of foods with antimicrobial residues. It is further stressed that there is a need for stricter regulation regarding the use of veterinary drugs in particular antimicrobials in the poultry industry as well as the inspection of meat for residues prior to marketing.

Key words: Broiler chicken, antimicrobial residues, Zanzibar