Detection and determination of tetracycline residue levels in beefg at Addis Ababa, D/Z, & Nazareth Slaughtered houses

No Thumbnail Available



Journal Title

Journal ISSN

Volume Title



A cross-sectional study was conducted from October 2006 to May 2007 to investigate the proportion of tetracycline residue levels in beef at Addis Ababa, Debre Zeit and Nazareth slaughterhouses. A total of 384 muscle and kidney samples were randomly collected from slaughtered cattle in the respective slaughterhouses. The samples were qualitatively screened for tetracycline residues by thin layer chromatography using a suitable silica gel (Merck silica gel 60 plates).The positive samples were then further analyzed by using high performance liquid chromatography (HPLC) Shimadzu Model Class-VP series with an electron diode array detector. The result of this study indicated that oxytetracycline residues previously detected in thin layer chromatography were detected in all samples by HPLC. A given sample was regarded as positive for tetracycline if its retention time and peak corresponded to that of the standard. Out of the 384 samples that were analyzed for tetracycline residues 274 (71.35%) had detectable oxytetracycline residues. Tetracycline and doxycycline were not detected. At Addis Ababa slaughterhouse, 120 (93.75%) of kidney and beef samples were positive for oxytetracycline. In Debre Zeit 48 (37.5%) of kidney and beef samples were also positive for oxytetracycline while from Nazareth slaughterhouse 106 (82.81%) of kidney and beef were positive for oxytetracycline. The mean (p>0.05) residue levels of oxytetracycline for the three slaughterhouses studied in muscle were as follows: Addis Ababa 108.34μg/kg, Nazareth 64.85μg/kg and 15.916μg/kg at Debre Zeit while in kidney samples were (p<0.05): 99.02 μg/kg in Addis Ababa, 109.35μg/kg in Nazareth and 112.53μg/kg in Debre Zeit slaughterhouses. The oxytetracycline positive samples, which showed residues of oxytetracycline above maximum residue limits (100μg/kg) in muscle samples, were 58 (48.33%) at Addis Ababa slaughterhouse and 51 (48.11%) at Nazareth slaughterhouse and 1 (0.9%) in the kidney samples of Nazareth slaughterhouse. At Debre Zeit slaughterhouse no samples were above the maximum residue limit. The results obtained confirmed that oxytetracycline was heavily and indiscriminately used in the fattening farms, small scale fattening farms, pastoralists and other animal owners. The results also suggest that the recommended withdrawal time was not strictly applied. Results of the present study could serve as a preliminary base line information for veterinary authorities, drug administration and quality control authority, other concerned organizations and professionals to take measures on control x and prevention of drug residues; as well as the consumer to be aware of the possible drug residue risks through consumption of unsafe animal products.



Tetracycline, residue, beef, kidney