Hök K
Department of Medical Microbial Ecology, Karolinska Institutet, Stockholm, Sweden.
Acta Vet Scand. 1993;34(4):345-56. doi: 10.1186/BF03548177.
The onset and pattern of the clinical signs of feline corona virus (FCoV) infection in cats were studied in a setting behind an isolation barrier. Two FCoV-seropositive cats were the source of the infection, and 3 barrier reared cats - initially FCoV-seronegative - were the recipients. The first clinical sign in the recipients appeared 11 days after contact with the source of infection. After 2 years 1 male and 1 female of the recipients started to breed. Their offspring developed clinical signs of disease at an age of 4-5 weeks. A pattern of recurring upper respiratory tract signs and conjunctivitis at intervals of about 4 months was observed in both the recipients and their offspring, while CNS dependent signs and wasting remained or got worse, once developed. Once demonstrated, FCoV antigen persisted in membrana nictitans throughout the investigation, and was found in all cats but 4 (90%). The offspring died during 2 periods, around the first week of life (9/37), and at 3-5 months of age (5/25). For comparison 3 offspring were euthanized at an age of 1 day and 16 offspring at an age of 3-6 months. FCoV antigen was demonstrated in all organs investigated (100%) from offspring dying during the first period, and in 97% from those dying during the second period. For the offspring euthanized during the same 2 periods the corresponding findings were 95% and 85%. Offspring euthanized between 9 and 17 months (4 kittens) had antigen in 67% of all investigated organs. The incidence of FCoV antigen in almost every organ in the investigated newborn kittens suggests an intrauterine infection. The demonstration of FCoV antigen in all euthanised cats, suggests a persistent infection. Virus was cultivated from membrana nictitans, that was FCoV antigen positive in the M3 test.
在隔离屏障后的环境中研究了猫感染猫冠状病毒（FCoV）的临床症状的发作和模式。两只FCoV血清阳性猫是感染源，3只最初FCoV血清阴性的屏障饲养猫是受体。受体中的第一个临床症状在与感染源接触11天后出现。2年后，受体中的1只雄性和1只雌性开始繁殖。它们的后代在4 - 5周龄时出现疾病临床症状。在受体及其后代中均观察到约每4个月出现一次的反复上呼吸道症状和结膜炎模式，而一旦出现，中枢神经系统相关症状和消瘦会持续或加重。一旦检测到，FCoV抗原在整个研究过程中持续存在于瞬膜中，除4只猫外（90%）在所有猫中均被发现。后代在两个时期死亡，出生后第一周左右（9/37），以及3 - 5月龄时（5/25）。作为对照，3只后代在1日龄时被安乐死，16只后代在3 - 6月龄时被安乐死。在第一时期死亡的后代的所有调查器官中均检测到FCoV抗原（100%），在第二时期死亡的后代中为97%。在同一两个时期被安乐死的后代中，相应的发现分别为95%和85%。在9至17月龄之间被安乐死的后代（4只小猫）中，67%的所有调查器官中存在抗原。在所调查的新生小猫几乎每个器官中FCoV抗原的出现表明存在宫内感染。在所有安乐死的猫中检测到FCoV抗原，表明存在持续性感染。病毒从瞬膜中培养出来，该瞬膜在M3试验中FCoV抗原呈阳性。
