Dickins M Avery, Franklin Sharon, Stefanova Rossina, Schutze Gordon E, Eisenach Kathleen D, Wesley Irene, Cave M Donald
Department of Anatomy, University of Arkansas for Medical Sciences, Little Rock 72205, USA.
J Food Prot. 2002 Jun;65(6):957-62. doi: 10.4315/0362-028x-65.6.957.
Campylobacter spp. are a major contaminant of poultry. Eating undercooked chicken and handling raw poultry have been identified as risk factors for campylobacteriosis in humans. Previous studies have found Campylobacter spp. on 90% of poultry carcasses. In the present study, pulsed-field gel electrophoresis (PFGE) was used to assess the genetic diversity of strains on retail poultry carcasses. PFGE patterns of isolates from campylobacteriosis cases were compared to those from the poultry isolates. Over a 1-year study period (March 2000 through February 2001), whole fresh young chickens (n = 72) were obtained from three retail outlets in an urban community in the south-central United States. Campylobacter spp. were isolated from 82% of these carcasses. Strains (n = 70) were defined on the basis of their PFGE pattern. Sixty-seven percent of the carcasses from which Campylobacter spp. were isolated were contaminated with more than one PFGE-distinguishable strain. During the 1-year study period, most of the PFGE patterns (59%) were limited to isolates obtained from a single carcass. Forty-one percent of the PFGE-distinguishable strains were recovered from more than one carcass. Ninety-seven percent of the carcasses contaminated with the same strain were purchased at the same time from the same store. To examine the degree of genetic stability, four strains were followed in vitro over an estimated 1,000 doublings. The PFGE pattern of one of these isolates underwent minor changes during in vitro growth. The data indicate extensive variability in the PFGE patterns of Campylobacter spp. isolated from humans and from poultry carcasses. In spite of difficulties caused by such diversity and the fact that some carcasses are contaminated with more than one strain, the pattern variation provides a useful method for linking a particular strain to its source.
弯曲杆菌属是家禽的主要污染物。食用未煮熟的鸡肉和处理生禽肉已被确定为人类弯曲杆菌病的危险因素。先前的研究发现，90%的家禽胴体上存在弯曲杆菌属。在本研究中，脉冲场凝胶电泳（PFGE）被用于评估零售家禽胴体上菌株的遗传多样性。将弯曲杆菌病病例分离株的PFGE图谱与家禽分离株的图谱进行比较。在为期1年的研究期间（2000年3月至2001年2月），从美国中南部一个城市社区的三个零售点获取了整只新鲜幼鸡（n = 72）。从82%的这些胴体中分离出了弯曲杆菌属。根据PFGE图谱定义了菌株（n = 70）。分离出弯曲杆菌属的胴体中，67%被一种以上PFGE可区分的菌株污染。在1年的研究期间，大多数PFGE图谱（59%）仅限于从单个胴体获得的分离株。41%的PFGE可区分菌株从不止一个胴体中分离得到。97%被相同菌株污染的胴体是在同一时间从同一家商店购买的。为了检查遗传稳定性程度，在体外对四个菌株进行了大约1000次倍增的跟踪。其中一个分离株的PFGE图谱在体外生长过程中发生了微小变化。数据表明，从人类和家禽胴体分离出的弯曲杆菌属的PFGE图谱存在广泛变异性。尽管这种多样性带来了困难，而且一些胴体被一种以上菌株污染，但图谱变异为将特定菌株与其来源联系起来提供了一种有用的方法。
