Porcine proliferative enteropathy remains one of the most prevalent diseases in swine herds worldwide. This disease is caused by Lawsonia intracellularis, an intracellular bacterial pathogen that primarily colonizes the ileum. In this study we evaluated changes to the microbiome of the ileal mucosa, ileal digesta, cecal digesta and feces subsequent to challenge with L. intracellularis and to an oral live vaccine against L. intracellularis. Given that gut homogenates have been used since 1931 to study this disease, we also characterized the microbial composition of a gut homogenate from swine infected with L. intracellularis that was used as challenge material. The L. intracellularis challenge led to a dysbiosis of the microbiome of both the small and large intestine marked by an increase of pathobionts including Collinsella, Campylobacter, Chlamydia and Fusobacterium. This microbiome response could play a role in favoring L. intracellularis colonization and disease as well as potentially predisposing to other diseases. Vaccination altered both small and large intestine microbiome community structure and led to a significant 3.03 log10 reduction in the amount of L. intracellularis shed by the challenged pigs. Vaccination also led to a significant decrease in the abundance of Collinsella, Fusobacterium and Campylobacter among other microbial changes compared to non-vaccinated and challenged animals. These results indicate that L. intracellularis infection is associated with broad changes to microbiome composition in both the large and small intestine, many of which can be mitigated by vaccination.

中文翻译：

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口服疫苗可减少胞内劳森菌挑战对猪小肠和大肠微生物组的影响

猪增殖性肠病仍然是全世界猪群中最流行的疾病之一。这种疾病是由胞内劳森菌引起的，这是一种主要定植于回肠的细胞内细菌病原体。在这项研究中，我们评估了细胞内乳杆菌攻击和针对细胞内乳杆菌口服活疫苗后回肠粘膜、回肠食糜、盲肠食糜和粪便微生物组的变化。鉴于自 1931 年起就使用肠道匀浆来研究这种疾病，我们还对感染胞内乳杆菌的猪的肠道匀浆的微生物组成进行了表征，该猪被用作攻击材料。胞内乳杆菌的攻击导致小肠和大肠微生物群失调，其特征是包括柯林斯氏菌、弯曲杆菌、衣原体和梭杆菌在内的病原体增加。这种微生物组反应可能在促进胞内乳杆菌定植和疾病方面发挥作用，并可能诱发其他疾病。疫苗接种改变了小肠和大肠微生物群落结构，并使受攻击猪排出的胞内乳杆菌数量显着减少 3.03 log10。与未接种疫苗和受到攻击的动物相比，疫苗接种还导致柯林斯氏菌、梭杆菌和弯曲杆菌等微生物变化的丰度显着下降。这些结果表明，胞内乳杆菌感染与大肠和小肠微生物组组成的广泛变化有关，其中许多变化可以通过疫苗接种来减轻。