【摘要】 自1960年春季和冬季,在四川西北草地发现绵羊的一种急性败血性传染病。在羔羊及成年羊中均有较高的发病率及死亡率。病原菌易自尸体血液及各组织器官中分离出纯培养。病原菌大小为0.7—0.9×0.6—0.8微米,革兰氏染色阳性,在渗出液及组织中多呈单个、成对及短链排列,荚膜清晰可见。为需氧及兼性厌氧菌,体外培养在培养基中需加入血清或血液。其生化特性在糖发酵方面能发酵葡萄糖、乳糖、蔗糖、麦芽糖和山梨醇产酸但不产气,不发酵蕈糖、鼠李糖、棉实糖、伯胶糖、廿露醇、肌醇和菊糖。在血琼脂上常呈β型溶血。不能溶解人和绵羊血液中的纤维素。不能水解马尿酸钠及马栗苷,但可水解淀粉。在蛋白胨肉汤中产 NH₃。不能液化明胶。在45℃,氯化钠6.5%,40%胆汁血琼脂,及0.1%美蓝牛乳中不生长。10%胆汁肉汤中不被溶解。在葡萄糖肉汤中最终 pH为4.9。沉淀试验按 Lancefield 分类系统属 G 群。小白鼠、家鸽、家兔和山羊对本菌易感,豚鼠、猪和马则具有抵抗力。皮下、静脉和呼吸道人工接种成年绵羊75只,发病率为100%,死亡率为81.4%,口服接种4只仅其中1只发病。接触感染3只有2只发病死亡。绵羊发病后体温升高到40.5—41.5℃,同时呈现精神沉郁、食欲减损、咳嗽、流泪和自鼻孔流出浆液性鼻涕,以后转为粘液-浓性鼻涕。在发病过程中,红血球渐有减少,白血球则显著增加由发病前的9,000—15,000/mm³。增至20,000—30,000/mm³,个别病例甚至达50,000/mm³。以上。在白血球分类计数中,嗜中性球由30—50%增至60—80%,少数可达90%以上。共中幼稚型和杆状核者占1/3—1/2。病理解剖变化,依据病程不同,可分为急性（败血）型及亚急性（胸）型。前者病程为2—5天,病变以浆膜与粘膜出血、实质器官变质、全身淋巴结充血、出血同髓样肿胀,脾髓软化,胆囊肿大等为主。后者病程为1—2周,有明显的纤维素性胸膜肺炎及腹膜炎。病理组织学观察,见病原链球菌存在于体内各组织中及血液中,引起血管和淋巴管的损伤,血液循环及淋巴循环障碍,实质器官的实质细胞营养不良与渐进性坏死,以及间叶结缔组织的水肿、坏死和溶解。与此同时,机体防卫反应虽有吞噬细胞的剧烈增生、活动与吞噬,但由于细菌具有荚膜和迅速大量繁殖的结果,其产生的毒素终于使机体屏障机构的瓦解,导致毒血症及败血症而死亡。更多还原

【Abstract】 Since the spring of 1960,an apparently infectious disease has been prevailing among sheep in the range of North-western part of Szechuan,attacking both lambs and adult sheep.The causal bacterium was found to be a streptococcus belonging to the Group C of Lancefleld.It was very similar to Strep.Zoo-epidemicus in several respects except that it did not ferment salicin and caused milk coagulation. The disease usually run an acute course with symptoms of septicemia,causing death in 2-5 days.At other times,it took a subacute form,menifested by rise of temperature,re- duced appetite,cough,lachrimation and profuse nasal discharge which was serious at first, then mucoid and finally muco-purulent.Leucocytosis with left depletion of neutrophils was marked.In this form of disease,most animals died usually in 1-2 weeks. Postmortem examination in acute cases revealed congestion and hemorrhage in internal organs.Spleen was softened and enlarged,and the gall-bladder distended markedly.In sub- acute cases the most prominent changes consisted of serofibrinous pleuro-pneumonia and peritonitis.Lymph nodes were swollen and edematous.Microscopically,there were marked edema and leucocytic infiltration in connective tissues.Parenchymatous organs showed de- generation,cellular infiltration,necrobiosis and hemorrhages of various extent.A great number of streptococcus were seen in the blood,as well as pulmonary and pleural exudates,many of them being found within the phagocytes of various kinds.Toxemia and/or septicemia were as- sumed to be the cause of death.更多还原