National Animal Disease Center, Agricultural Research Service, USDA, Ames, IA, United States.
National Animal Disease Center, Agricultural Research Service, USDA, Ames, IA, United States; Oak Ridge Institute for Science and Education, Oak Ridge, TN, United States.
Vet Microbiol. 2023 Sep;284:109841. doi: 10.1016/j.vetmic.2023.109841. Epub 2023 Aug 1.
Bordetella bronchiseptica and Streptococcus suis are widely distributed swine pathogens. B. bronchiseptica is a primary pathogen and causes atrophic rhinitis and bronchopneumonia. S. suis is a contributing agent to porcine respiratory disease complex and causes systemic diseases including arthritis, meningitis, polyserositis, and septicemia. Colonization with B. bronchiseptica has been associated with increased colonization by other pathogenic bacteria and increased disease severity with viral and bacterial pathogens. It has also been reported to predispose cesarean derived, colostrum deprived (CDCD) piglets to S. suis systemic disease. Here, we evaluated the role of B. bronchiseptica colonization on S. suis colonization, dissemination, and disease in one study using conventional pigs and another using CDCD pigs. Pigs were challenged with S. suis, B. bronchiseptica, or B. bronchiseptica followed by S. suis. Incidence of S. suis disease was not increased in either study for animals pre-inoculated with B. bronchiseptica. Nasal colonization with S. suis was increased in coinfected animals, while B. bronchiseptica was similar between mono- and co-infected animals. Although increased S. suis disease was not seen in coinfected pigs, there is evidence that B. bronchiseptica can increase colonization with S. suis, which may contribute to enhanced disease when animals are stressed or immunocompromised.
支气管败血波氏杆菌和猪链球菌广泛存在于猪群中，是两种主要的病原体。支气管败血波氏杆菌是原发性病原体，可引起萎缩性鼻炎和支气管肺炎。猪链球菌是猪呼吸道疾病综合征的致病因子之一，可引起关节炎、脑膜炎、多发性浆膜炎和败血症等全身性疾病。支气管败血波氏杆菌的定植与其他致病细菌的定植增加以及与病毒和细菌病原体相关的疾病严重程度增加有关。此外，它还会使剖腹产、缺乏初乳（CDCD）的仔猪易患猪链球菌系统性疾病。在此，我们使用常规猪和 CDCD 猪进行了一项研究，评估了支气管败血波氏杆菌定植对猪链球菌定植、传播和疾病的影响。猪只接受了猪链球菌、支气管败血波氏杆菌或支气管败血波氏杆菌后再接种猪链球菌的挑战。在这两项研究中，预先接种支气管败血波氏杆菌的动物的猪链球菌病发病率均未增加。在混合感染动物中，猪链球菌的鼻腔定植增加，而单感染和混合感染动物之间的支气管败血波氏杆菌相似。虽然混合感染猪未出现更严重的猪链球菌病，但有证据表明，支气管败血波氏杆菌可增加猪链球菌的定植，当动物处于应激或免疫功能低下时，可能会导致疾病加重。
