Abstract
this study is aimed to evaluate the level of enrofloxacin and oxytetracycline residues in chicken meat and giblets and the effect of freezing and heat treatment methods on reduction of these residues. One hundred random samples of chicken breast, thigh, kidney and liver (25 of each) were collected from different chicken slaughter shops located in Sharkia Governorate for evaluation of their enrofloxacin and oxytetracycline residues. The collected samples were examined by using qualitative method by antimicrobial assay and quantitative method by High Performance Liquid Chromatography (HPLC) in addition to the effect of heat treatment (boiling and freezing) on these residues was studied. The obtained results revealed that the incidence of antibiotic residues in chicken breast, thigh, kidney and liver were 0%, 8%, 20% and 20% respectively by qualitative method and by HPLC the level of enerofloxacine 109, 122 and 202 ppb in thigh, liver and kidney respectively; meanwhile oxytetracycline level were 236, 523 and 1153 ppb in thigh, liver and kidney respectively. The results indicated that 75% of the positive samples not exceeded the MRL of enrofloxacin and oxytetracycline residues. Regarding to treatment trials either by freezing for (1month, 3month and 6 months) or by heating (boiling, roasting or frying) The reduction percent of residue levels was calculated and the public health significance and some recommendations to control such antibiotic residue in chicken tissues for human safety were discussed.

Key words: chicken meat, gizzard, liver, enrofloxacin, oxytetracycline, HPLC