Antibiotic use in food animals: determination of enrofloxacin residue in chicken tissue

Background: Poultry farmers in Nigeria employ the use of various antibiotics with or without the guidance of veterinarians, to promote growth and prevent infections in poultry. Although antibiotics benefit most of its uses, this has led to the accumulation of toxic antibiotic residues in edible poultry products destined for human consumption.

Objective: The present study was aimed at determining the residual amounts of enrofloxacin in chicken muscle samples.

Method: Forty birds were obtained from commercial poultries in Lagos State and randomly allotted into 7 groups. They were humanely sacrificed, dissected and 10.0 g of muscle tissue was sectioned from each drumstick and homogenized in a porcelain mortar. 5.0 g of the homogenate was weighed and transferred into a 5 ml plain sample bottle and processed for analysis by high performance liquid chromatography to determine the amount of enrofloxacin in the tissues.

Results: Enrofloxacin was detected in all samples from the four farms. The mean concentration of enrofloxacin ranged from 23.5 to 88.1 µg/g in all the 7 samples analyzed; these values were higher than the maximum residue level of 0.1 μg/ug in Europe and 0.3 μg/ug in the United States of America. 

Conclusion: This study confirmed misuse of enrofloxacin in poultry farms and emphasizes the need for stricter regulation regarding antibiotic use in poultry as well as the screening of chicken for residues before sale.

研究背景：尼日利亚家禽养殖户在有或无兽医指导的前提下，会使用各类抗生素以促进家禽生长、预防家禽感染。尽管抗生素在多数应用场景中具有益处，但该做法导致供人类食用的可食用家禽产品中积累了具有毒性的抗生素残留。

研究目的：本研究旨在测定鸡肉样本中的恩诺沙星（enrofloxacin）残留量。

研究方法：从拉各斯州的商业家禽养殖场采集40只家禽，将其随机分为7组。以人道方式处死家禽并进行解剖，从每只鸡腿取10.0g肌肉组织，置于瓷质研钵中匀浆。称取5.0g匀浆物转移至5ml普通样品瓶中，采用高效液相色谱法（high performance liquid chromatography）进行分析，以测定组织中恩诺沙星的含量。

研究结果：本研究在4个养殖场的全部样本中均检出恩诺沙星。所分析的7份样本中，恩诺沙星的平均浓度范围为23.5至88.1 µg/g；该数值高于欧洲规定的0.1 μg/ug以及美国规定的0.3 μg/ug的最大残留限量（maximum residue level）。

研究结论：本研究证实了家禽养殖场存在恩诺沙星的滥用情况，并强调需对家禽养殖中的抗生素使用实施更严格的监管，同时需在鸡肉上市前对其残留情况进行筛查。