Jensen A N, Dalsgaard A, Baggesen D L, Nielsen E M
Danish Institute for Food and Veterinary Research, Department of Microbiological Food Safety, Bülowsvej 27, DK-1790 Copenhagen V, Denmark.
Vet Microbiol. 2006 Aug 25;116(1-3):96-105. doi: 10.1016/j.vetmic.2006.03.006. Epub 2006 May 11.
The occurrence and species distribution of thermophilic Campylobacter was investigated in organic outdoor pigs. An increased exposure of outdoor pigs to C. jejuni from the environment may cause a shift from a normal dominance of C. coli to more C. jejuni, which may imply a concern of reduced food safety. Bacteriological methods for determination of Campylobacter excretion level were combined with colony-blot hybridization and real-time PCR for specific detection of C. jejuni in pigs. Campylobacter was isolated from pigs (n=47), paddock environment (n=126) and wildlife (n=44), identified to species by real-time PCR and sub-typed by serotyping (Penner) and pulse-field gel electrophoresis (PFGE) genotyping. All pigs excreted Campylobacter (10(3)-10(7) CFU g(-1) faeces) from the age of 8-13-weeks old. C. jejuni was found in 29% of pigs in three consecutive trials and always in minority to C. coli (0.3-46%). C. jejuni and C. coli were isolated from 10% and 29% of the environmental samples, respectively, while crow-birds and rats harboured C. jejuni. Individual pigs hosted several strains (up to nine serotypes). The paddock environment was contaminated with C. coli serotypes similar to pig isolates, while most of the C. jejuni serotypes differed. C. jejuni isolates of different origin comprised few similar serotypes, just one identical genotype was common between pigs, environment and birds. In conclusion, the occurrence of C. jejuni varied considerably between the three groups of outdoor pigs. Furthermore, transfer of C. jejuni to the outdoor pigs from the nearby environment was not predominant according to the subtype dissimilarities of the obtained isolates.
对户外有机饲养猪中嗜热弯曲杆菌的发生情况及菌种分布进行了调查。户外猪从环境中接触空肠弯曲杆菌的增加可能会导致从正常情况下结肠弯曲杆菌占主导转变为空肠弯曲杆菌增多，这可能意味着食品安全问题。将用于测定弯曲杆菌排泄水平的细菌学方法与菌落杂交和实时荧光定量PCR相结合，用于猪中空肠弯曲杆菌的特异性检测。从猪（n = 47）、牧场环境（n = 126）和野生动物（n = 44）中分离出弯曲杆菌，通过实时荧光定量PCR鉴定菌种，并通过血清分型（彭纳分型）和脉冲场凝胶电泳（PFGE）基因分型进行亚型分析。所有猪从8至13周龄开始排泄弯曲杆菌（10³ - 10⁷ CFU g⁻¹粪便）。在连续三次试验中，29%的猪体内发现有空肠弯曲杆菌，且其数量始终少于结肠弯曲杆菌（0.3% - 46%）。分别从10%和29%的环境样本中分离出空肠弯曲杆菌和结肠弯曲杆菌，而乌鸦和大鼠体内携带空肠弯曲杆菌。个体猪携带多种菌株（多达九种血清型）。牧场环境被与猪分离株相似的结肠弯曲杆菌血清型污染，而大多数空肠弯曲杆菌血清型不同。不同来源的空肠弯曲杆菌分离株仅有少数相似的血清型，在猪、环境和鸟类之间仅有一种相同的基因型。总之，三组户外猪中空肠弯曲杆菌的发生情况差异很大。此外，根据所获得分离株的亚型差异，空肠弯曲杆菌从附近环境转移到户外猪中并非主要途径。
