Campylobacter (C.) species are the most common bacterial cause of foodborne diarrhea in humans. Despite colonization, most animals do not show clinical signs, making recognition of affected flocks and disruption of the infection chain before slaughter challenging. Turkeys are often cocolonized with C. jejuni and C. coli. To understand the pathogen-host-interaction in the context of two different Campylobacter species, we compared the colonization patterns and quantities in mono- and co-colonized female commercial turkeys. In three repeated experiments we investigated the impact on gut morphology, functional integrity, and microbiota composition as parameters of gut health at seven, 14, and 28 days post-inoculation. Despite successful Campylobacter colonization, clinical signs or pathological lesions were not observed. C. coli persistently colonized the distal intestinal tract and at a higher load compared to C. jejuni. Both strains were isolated from livers and spleens, occurring more frequently in C. jejuni- and co-inoculated turkeys. Especially in C. jejuni-positive animals, translocation was accompanied by local heterophil infiltration, villus blunting, and shallower crypts. Increased permeability and lower electrogenic ion transport of the cecal mucosa were also observed. A lower relative abundance of Clostridia UCG-014, Lachnospiraceae, and Lactobacillaceae was noted in all inoculated groups compared to controls. In sum, C. jejuni affects gut health and may interfere with productivity in turkeys. Despite a higher cecal load, the impact of C. coli on investigated parameters was less pronounced. Interestingly, gut morphology and functional integrity were also less affected in co-inoculated animals while the C. jejuni load decreased over time, suggesting C. coli may outcompete C. jejuni. Since a microbiota shift was observed in all inoculated groups, future Campylobacter intervention strategies may involve stabilization of the gut microbiota, making it more resilient to Campylobacter colonization in the first place.

中文翻译：

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空肠弯曲杆菌和大肠杆菌定植对雌性火鸡肠道形态、功能完整性和微生物群组成的影响

弯曲杆菌 (C.) 物种是人类食源性腹泻最常见的细菌原因。尽管有定植，但大多数动物没有表现出临床症状，这使得在屠宰前识别受影响的鸡群和破坏感染链具有挑战性。火鸡经常被空肠弯曲菌和大肠杆菌感染。为了了解两种不同弯曲杆​​菌属的病原体-宿主相互作用，我们比较了单定殖和共定殖雌性商业火鸡的定殖模式和数量。在三个重复实验中，我们研究了在接种后 7、14 和 28 天对肠道形态、功能完整性和微生物群组成的影响，作为肠道健康的参数。尽管弯曲杆菌定植成功，但未观察到临床症状或病理损伤。C。与空肠弯曲菌相比，大肠杆菌持续在远端肠道定植，并且负荷更高。两种菌株均从肝脏和脾脏中分离出来，在空肠梭菌和共同接种的火鸡中更常见。特别是在空肠弯曲菌阳性动物中，易位伴有局部嗜异性浸润、绒毛变钝和较浅的隐窝。还观察到盲肠粘膜的通透性增加和低电离子传输。与对照组相比，在所有接种组中都注意到梭菌 UCG-014、毛螺菌科和乳杆菌科的相对丰度较低。总之，空肠弯曲菌会影响肠道健康，并可能干扰火鸡的生产力。尽管盲肠负荷较高，但大肠杆菌对研究参数的影响不太明显。有趣的是，肠道形态和功能完整性在共同接种的动物中也受到较小的影响，而空肠弯曲菌的负荷随着时间的推移而下降，这表明大肠杆菌可能胜过空肠弯曲菌。由于在所有接种组中都观察到了微生物群的变化，未来的弯曲杆菌干预策略可能涉及稳定肠道微生物群，使其首先对弯曲杆菌定植更具弹性。