实验性鸭疫里氏杆菌病病理学动态变化

对90只11日龄鸭通过颈部皮下人工接种鸭疫里氏杆菌,分别在感染后12h、24h、36h、48h、60h、72h剖杀,观察其动态病理变化。结果表明,鸭在感染24h后就开始出现浆液纤维素性心包炎、肝周炎、气囊炎,并持续整个病理过程。组织学病变主要为肝脏、心脏、脾脏、气囊等表面增厚,有大量浆液纤维素性渗出物,其中有嗜中性粒细胞和单核细胞浸润;心肌细胞和肾小管上皮细胞颗粒变性,肝细胞脂肪变性和凝固性坏死,脾脏淋巴细胞减少,脑膜水肿充血。证实了鸭疫里氏杆菌主要侵害浆膜和肝脏,引起多发性浆膜炎和肝坏死。     

Alternative injection sites for a Pasteurella multocida bacterin

Seven different injection sites for a Pasteurella multocida bacterin were evaluated by measuring the immune response and the local tissue reaction. Injection into the ventral surface of the tail or subcutaneously along the dorsal midline of the neck were the most suitable procedures. Ease of application was judged subjectively, and the tail site was found to be easier to inject accurately than the subcutaneous neck site. The tail injection site was found to be the best overall when immune response, tissue reaction, and ease of application were all considered.     

Pasteurella anatipestifer infection in turkeys

In a case of excessive mortality in seven-week-old turkeys, the primary lesion at necropsy was severe fibrinous pericarditis and epicarditis. After 48 hours of incubation at 37 C, Pasteurella anatipestifer was isolated. The infection responded to antibiotic therapy with a combination of neomycin and oxytetracycline in the drinking water. The lesions suggested chlamydial infection, but cultural procedures for chlamydia were negative.     

雏鸭源多杀性巴氏杆菌的分离鉴定和荚膜PCR分型

本研究从河南某肉鸭养殖场感染鸭肝炎病毒的10日龄病死鸭肝脏中分离到一株致病菌,经菌落形态学观察、培养特性、生化反应、致病性回归试验和SPF鸡攻毒试验,结合多杀性巴氏杆菌(Pasteurella multocida,Pm) kmt1种特异性基因检测方法进行鉴定,并通过16S rRNA序列测定进行同源性分析.结果显示该分离株为Pm,命名为Pm-Y.致病性回归试验表明低浓度的Pm-Y只引起部分10日龄雏鸭发病死亡.SPF鸡攻毒试验显示,Pm-Y与国内标准强毒株C48-1的致病力相近,16S rRNA序列系统发育树分析表明Pm-Y与Pm多杀亚种和杀禽亚种亲缘关系最近.参考荚膜血清特异性基因hyaD-hyaC、bcbD、dcbF、ecbJ和fcbD合成引物,扩增荚膜血清型特异性基因,对Pm-Y进行荚膜分型鉴定为A型Pm.本研究是国内首例从感染鸭肝炎病毒10日龄雏鸭肝脏中分离到Pm的报道.     

鸭疫巴氏杆菌病的预防与治疗

鸭疫巴氏杆菌(Pasteurella anatipestifer,PA)病是家鸭、火鸡和多种禽类的一种高度接触性传染病,又称为新鸭病、鸭败血症、鸭疫综合征、传染性浆膜炎、鸭疫里雷默氏杆菌(Riemerella anatipestifer,RA)病。鸭疫巴氏杆菌病于1932年由Hendrickson J M.首次报道,我国郭玉璞等于1982年在北京首次报道,并对本病病原菌进行了分离和鉴定。     

人工感染鸭疫里默氏杆菌雏鸭部分血液指标的动态变化

20日龄天府肉鸭用鸭疫里默氏杆菌人工感染后,感染鸭发病率86%,死亡率70%;发病期红细胞脆性增大,血沉加快,血红蛋白、红细胞比容降低.     

鸭传染性浆膜炎免疫研究进展

鸭传染性浆膜炎是由鸭疫里氏杆菌(RA)又名鸭疫巴氏杆菌引起的一种严重危害雏鸭的传染病。本病呈急性败血症或慢性过程，以纤维素性心包炎、肝周炎、气囊炎、脑膜炎和干酪性输卵管炎为特征。1～8周龄雏鸭易感，恶劣环境条件可诱发此病。死亡率最高可达75％。慢性经过的鸭主要表现脑膜炎症状，即斜颈，生长缓慢成僵鸭，给养鸭业造成巨大的损失。　　药物防治是我国目前控制该病的主要措施。虽然药敏试验表明该菌对多种药物敏感，但实际防治效果并不理想；加上肉鸭在养殖全程均对该菌易感，要达到较好的治疗效果，必须反复投药，既增加了成本…     

鸭源多杀性巴氏杆菌在人工感染雏鸭体内的动态研究

为探索多杀性巴氏杆菌在雏鸭体内的动态病理变化,用小鼠复壮鸭源多杀性巴氏杆菌,经测定其滴鼻途径的LD50=1×10-4.5/0.2 mL,口服途径的LD50=1×10-2.375/0.2mL.用100 LD50剂量,以口服、滴鼻途径分别感染雏鸭,于感染后6 h、12 h、18 h和24 h取心、肝、肺、肾及胸腺进行组织活菌计数.口服和滴鼻感染后12 h,从胸腺、肝、心、肺检测到生长繁殖的病原菌,18 h从口服感染组的肾脏检出目标菌,24 h从滴鼻组的肾脏检出目标菌.口服感染12 h,胸腺中菌数最高,达5.33×103 CFU/g,依次是肝、肺、心、肾.滴鼻感染12h,肺中菌数最高,达5.00×103 CFU/g,依次是胸腺、肝、心、肾.24 h均以胸腺菌数最高.表明检测体内鸭巴氏杆菌抗原或分离病原菌,首选器官是胸腺和肺,其次是肝、心.同时取心、肝、肺、肾、脾、胸腺、法氏囊、腺胃和十二指肠制作病理切片.消化道途径感染出现病变的最早时间是侵入后6 h,呼吸道途径感染出现病变的时间小于6 h.口服途径感染雏鸭后6 h,各器官都表现以充血为主要特征的轻微病理变化,6 h～12 h表现以细胞肿胀、开始细胞变性为特征的病理变化.12 h～18 h表现细胞变性加剧,开始核浓缩、核碎裂为特征的病理变化.18 h～24 h表现核浓缩、核碎裂加剧,细胞溶解的细菌损伤病理,以及淋巴细胞浸润、免疫器官网状内皮细胞增生相伴的免疫损伤.滴鼻途径的病理变化与口服途径相似,但病理进程有所提前.鸭多杀性巴氏杆菌对胸腺、脾、法氏囊等免疫器官造成病理损伤,以胸腺和脾脏的损伤较为严重.     

武汉地区鸭疫巴氏杆菌的分离鉴定

２０００年３～５月,对送检于华中农业大学兽医院的病鸭进行病理剖检及细菌分离鉴定,确定送检病例５０％以上由鸭疫巴氏杆菌（ＰＡ）引起,其发病日龄为７～５０日龄。从病鸭的脑脊液、心血、肝等均易分离到ＰＡ。药敏试验显示所有菌株对氯霉素高度敏感。此次试验结果说明,在武汉地区鸭疫巴氏杆菌确已存在,并已成为严重危害当地养鸭业的重要疾病之一。     

Spondylitis in turkeys associated with experimental Pasteurella anatipestifer infection.

Nine previously vaccinated turkeys were inoculated intravenously with Pasteurella anatipestifer, and blood samples were taken periodically to evaluate the potential of chronically infected turkeys to serve as reservoirs of infection for blood-feeding arthropod vectors. Vertebral osteomyelitis (spondylitis), as yet unreported in the literature in association with infection with the organism, was found in the thoracic vertebrae of five out of nine inoculated turkeys, and P. anatipestifer was isolated from the thoracic vertebrae of three of the five. The organism was isolated from the peripheral blood of six turkeys 24 hours postinoculation and from the peripheral blood of one turkey 7 days postinoculation. The organism was also isolated from the heart blood of two birds at necropsy--from one at 21 days and, following an intramuscular injection of dexamethasone, from the other turkey at 38 days postinoculation.     

鸭疫里默氏杆菌明胶酶对雏鸭免疫功能影响的研究

为研究鸭疫里默氏杆菌明胶酶对雏鸭免疫功能的影响,本研究将2000 u明胶酶经颈静脉注射10日龄健康鸭建立动物模型,测定了模型动物的部分免疫指标。结果显示,注射明胶酶的雏鸭外周血T淋巴细胞非特异性酯酶阳性率、白细胞杀菌指数、红细胞C3bR花环率、血清溶血和杀菌活性、脾淋巴细胞的增殖和分泌IgG能力等显著低于阴性和空白对照组(p0.05或p0.01);明胶酶可导致雏鸭脾脏严重损害,脾中央动脉内皮细胞肿胀、脱落,淋巴细胞变性、坏死及细胞核膜不规则与染色质周边浓集。结果表明,鸭疫里默氏杆菌明胶酶对雏鸭的免疫功能具有损害作用。     

鸭疫里默氏菌感染对雏鸭部分免疫学指标的影响

给10日龄健康鸭颈部皮下接种鸭疫里默氏菌建立感染的动物模型,于24h、48h、72h、96h测定雏鸭部分免疫学指标。结果显示,鸭疫里默氏菌(RA)感染可导致T淋巴细胞活性,血清总补体活性,白细胞吞噬和杀菌功能,红细胞免疫功能降低,脾淋巴细胞增殖活性和分泌IgG能力随感染的严重程度增加而下降。研究结果表明,RA感染能引起雏鸭部分免疫功能的变化,具有免疫抑制作用。     

Infection of duck plague carriers with Pasteurella multocida and P. anatipestifer

Mallards (Anas platyrhynchos platyrhynchos) and white pekin ducks (Anas platyrhynchos domesticus) were infected with duck plague virus and challenged with LD20's of Pasteurella multocida and P. anatipestifer. There was no difference between mortality rates of duck plague-infected ducks and controls, suggesting that these organisms do not act synergistically under the conditions of our experiments. There was a difference of about 500-fold between the LD20 of P. multocida for mallards and that for white pekin ducks, indicating that mallards are much more susceptible to avian cholera than white pekin ducks.