INRA, UMR1313 Génétique Animale et Biologie Intégrative Jouy-en-Josas cedex, France.
Front Genet. 2012 Dec 14;3:261. doi: 10.3389/fgene.2012.00261. eCollection 2012.
Salmonella enterica serotypes Enteritidis and Typhimurium and Campylobacter jejuni are responsible for most cases of food poisoning in Europe. These bacteria do not cause severe disease symptoms in chicken, but they are easily propagated by symptomless chicken carriers which cannot be easily isolated. This animal tolerance is detrimental to food safety. In this particular case, increasing animal's resistance is not sufficient, since some animals considered as resistant are able to carry bacteria during several weeks without displaying disease symptoms. We review studies aimed at evaluating the resistance of chicken to Salmonella and Campylobacter intestinal colonization, either a few days or several weeks after infection. While studies of the genetic control of Campylobacter colonization are only beginning, mostly due to technical difficulties in infection protocols, genetic studies of Salmonella colonization have been conducted for now more than 20 years. They have initially reported an estimation of the genetic parameters associated with resistance to Salmonella colonization and are now aimed at identifying the genomic regions controlling variation of this trait in experimental lines and commercial populations. With the advent of high-throughput genomics, we are closer than ever to identify the true genes controlling resistance to Enterobacteria colonization in chicken. The comparison of genes involved in early resistance to intestinal colonization with genes controlling resistance to bacteria persistence several weeks after infection (i.e., carrier-state) should soon highlight the differences between the molecular mechanisms underlying those two distinct phenotypes. It will also be highly interesting to compare the genes or genomic regions controlling Campylobacter and Salmonella, in order to evaluate the feasibility of a selection conducted on both bacteria simultaneously.
肠炎沙门氏菌血清型肠炎和鼠伤寒以及空肠弯曲菌是导致欧洲大多数食物中毒的罪魁祸首。这些细菌在鸡中不会引起严重的疾病症状，但它们很容易在无症状的鸡携带者中传播，这些携带者不易被隔离。这种动物的耐受性对食品安全不利。在这种特殊情况下，增加动物的抵抗力是不够的，因为一些被认为具有抵抗力的动物能够在不表现出疾病症状的情况下携带细菌数周。我们回顾了评估鸡对沙门氏菌和空肠弯曲菌肠道定植的抵抗力的研究，这些研究要么在感染后几天，要么在感染后数周进行。虽然对空肠弯曲菌定植的遗传控制的研究才刚刚开始，主要是由于感染方案的技术困难，但对沙门氏菌定植的遗传研究已经进行了 20 多年。它们最初报告了与沙门氏菌定植抗性相关的遗传参数的估计，现在的目标是确定控制实验品系和商业群体中该性状变异的基因组区域。随着高通量基因组学的出现，我们比以往任何时候都更接近确定控制鸡肠内定居的 Enterobacteria 抗性的真正基因。将早期对肠道定植的抗性基因与控制感染后数周细菌持续存在的抗性基因（即携带状态）进行比较，应该很快就能突出这两种不同表型背后的分子机制之间的差异。比较控制空肠弯曲菌和沙门氏菌的基因或基因组区域，以评估同时对两种细菌进行选择的可行性，也将非常有趣。
