MALIGNANT CATARRHAL FEVER .1. RESPONSE OF AMERICAN CATTLE TO MALIGNANT CATARRHAL VIRUS ISOLATED IN KENYA

  • 1 January 1981
    • journal article
    • research article
    • Vol. 45  (1) , 70-76
Abstract
American cattle (53) were inoculated with malignant catarrhal fever virus isolated from a wildebeest in Kenya. Three animals had a mild form of the disease and recovered; 47 had the severe form of the disease. The other 3 did not react. Of the 47 cattle, 28 died, 16 were killed for the collection of specimens and 3 recovered. The incubation period for the 47 cattle ranged from 16-29 days and the course of the fatal disease for 28 cattle averaged 3-23 days. Virus titration of specimens from 9 infected steers yielded a mean titer of 104/TCID50[tissue culture median infective dose]/g for lymph nodes, 103 TCID50/ml for buffy coats and 102.3 TCID50/g for spleens. Smaller amounts of virus were found in the liver, kidneys, adrenals and thyroids. Malignant catarrhal fever virus was also found in nasal secretions and saliva of viremic cattle. Viral infectivity was shown in bovine buffy coat cells stored at 4.degree. C for 2 days but was immediately destroyed upon freezing even when glycerine or dimethylsulfoxide was added. Viral particles were not found in infected mammal tissues by EM. The disease was successfully transmitted in steers by intratracheal intubation and by aerosol inhalation but not by contact.