De Herdt P, Haesebrouck F, Ducatelle R, De Groote B, Devriese L A
Laboratory of Veterinary Bacteriology & Mycology, Faculty of Veterinary Medicine, University of Gent, Belgium.
Vet Microbiol. 1994 Aug 15;41(4):321-32. doi: 10.1016/0378-1135(94)90028-0.
In a first experiment, the relative virulence for pigeons of 5 strains of S. bovis was assessed by experimental inoculations. Two S. bovis serotype 1 strains, one serotype 2 strain and two serotype 3 strains were examined. One of the serotype 1 strains and the serotype 2 strain were isolated from pigeons that died from septicaemia. The other strains were isolated from cloaca samples of healthy pigeons. For each strain, 10-20 pigeons were intravenously inoculated with 1 x 10(9) CFU. Morbidity after infection with the serotype 1 and 2 strains varied between 75% and 90%. Disease signs included inability to fly, lameness, emaciation, production of slimy, green droppings, polyuria and sudden death. In groups of pigeons inoculated with the serotype 3 strains, morbidity was 0% and 6%, respectively. Results demonstrate that serotype 3 strains are less virulent for pigeons than serotype 1 and 2 strains. In a second experiment, bacteriological and histological examinations were performed on organs of pigeons serially killed between 1 and 10 days after experimental inoculation with an S. bovis serotype 3 strain of low virulence. Results were compared with results of studies carried out with a highly virulent serotype 1 strain. Notwithstanding bacterial spread and replication in various organs of inoculated pigeons, clinical disease was not observed and histological lesions were scarce and of limited extent.
在第一个实验中，通过实验接种评估了5株牛链球菌对鸽子的相对毒力。检测了2株1型牛链球菌、1株2型牛链球菌和2株3型牛链球菌。其中1株1型菌株和2型菌株是从死于败血症的鸽子中分离出来的。其他菌株是从健康鸽子的泄殖腔样本中分离出来的。对于每一株菌株，给10 - 20只鸽子静脉接种1×10⁹CFU。感染1型和2型菌株后的发病率在75%至90%之间。疾病症状包括无法飞行、跛行、消瘦、产生黏腻的绿色粪便、多尿和突然死亡。在接种3型菌株的鸽子组中，发病率分别为0%和6%。结果表明，3型菌株对鸽子的毒力低于1型和2型菌株。在第二个实验中，对实验接种低毒力3型牛链球菌菌株后1至10天内连续处死的鸽子的器官进行了细菌学和组织学检查。将结果与用高毒力1型菌株进行的研究结果进行了比较。尽管接种的鸽子的各种器官中细菌有扩散和繁殖，但未观察到临床疾病，组织学病变很少且范围有限。
