Antibiotic residues in milk and eggs of commercial and local farms at Chittagong, Bangladesh

Aim: The study was conducted to detection and determination of concentration or level of antibiotic residues in milk and egg of local and commercial farms at Chittagong during December 2011 to June 2012. Materials and Methods: A total of 400 (200 milk and 200 egg) samples were collected from local and commercial dairy cows and local scavenging and commercial poultry farms, respectively. Microbial inhibition test and thin layer chromatography were used for screening and ultra-high performance liquid chromatography was used to estimate the concentrations of antibiotic residues in samples. Results: Tetracycline, amoxicillin, and ciprofloxacin residues were significantly (p <= 0.05) higher in commercial farms than local. The boiling insignificantly (p>0.05) reduced residues level in milk and egg. The average concentrations of amoxicillin residue in local milk, commercial milk, local egg, and commercial egg were 9.84 mu g/ml, 56.16 mu g/ml, 10.46 mu g/g and 48.82 mu g/g, respectively, in raw samples and were reduced to 9.81 mu g/ml, 55.54 mu g/ml, 10.29 mu g/g, and 48.38 mu g/g, respectively, after boiling. Conclusions: Proper maintaining of the withdrawal period and development of active surveillance system are highly recommended for public health security.