Barba M, Stewart A J, Passler T, Wooldridge A A, van Santen E, Chamorro M F, Cattley R C, Hathcock T, Hogsette J A, Hu X P
Department of Clinical Sciences, Auburn University, Auburn, AL.
J Vet Intern Med. 2015 Mar-Apr;29(2):636-43. doi: 10.1111/jvim.12545.
The route of Corynebacterium pseudotuberculosis infection in horses remains undetermined, but transmission by insects is suspected.
To investigate house flies (Musca domestica L.) as vectors of C. pseudotuberculosis transmission in horses.
Eight healthy, adult ponies.
Randomized, controlled, blinded prospective study. Ten wounds were created in the pectoral region where cages for flies were attached. Three ponies were directly inoculated with C. pseudotuberculosis. Four ponies were exposed for 24 hours to 20 hours C. pseudotuberculosis-inoculated flies. One negative control pony was exposed to noninoculated flies. Ponies were examined daily for swelling, heat, pain, and drainage at the inoculation site. Blood was collected weekly for CBC and biochemical analysis, and twice weekly for synergistic hemolysis inhibition titers.
Clinical signs of local infection and positive cultures were observed in 7/7 exposed ponies and were absent in the negative control. In exposed ponies, peak serologic titers (1:512 to 1:2,048) were obtained between days 17 and 21. Seroconversion was not observed in the negative control. Neutrophil counts were higher in the positive and fly-exposed groups than in the negative control (P = .002 and P = .005) on day 3 postinoculation. Serum amyloid A concentrations were higher in the positive control than in the negative control and fly-exposed ponies on days 3 (P < .0001) and 7 (P = .0004 and P = .0001). No differences were detected for other biochemical variables.
House flies can serve as mechanical vectors of C. pseudotuberculosis and can transmit the bacterium to ponies.
马感染伪结核棒状杆菌的途径尚未确定，但怀疑是通过昆虫传播。
研究家蝇（Musca domestica L.）作为马伪结核棒状杆菌传播媒介的情况。
8匹健康成年小马。
随机、对照、盲法前瞻性研究。在胸部区域制造10个伤口，并在伤口处安装蝇笼。3匹小马直接接种伪结核棒状杆菌。4匹小马暴露于接种了伪结核棒状杆菌的苍蝇24至20小时。1匹阴性对照小马暴露于未接种的苍蝇。每天检查小马接种部位的肿胀、发热、疼痛和引流情况。每周采集血液进行血常规和生化分析，每周两次进行协同溶血抑制效价检测。
7/7匹暴露的小马出现局部感染的临床症状且培养结果呈阳性，阴性对照未出现。在暴露的小马中，第17至21天获得了最高血清效价（1:512至1:2048）。阴性对照未观察到血清转化。接种后第3天，阳性组和苍蝇暴露组的中性粒细胞计数高于阴性对照（P = 0.002和P = 0.005）。第3天（P < 0.0001）和第7天（P = 0.0004和P = 0.0001），阳性对照的血清淀粉样蛋白A浓度高于阴性对照和苍蝇暴露的小马。其他生化变量未检测到差异。
家蝇可作为伪结核棒状杆菌的机械传播媒介，并可将该细菌传播给小马。
