RECRUDESCENCE OF INFECTIOUS BOVINE-RHINOTRACHEITIS VIRUS AND ASSOCIATED NEURAL CHANGES IN CALVES TREATED WITH DEXAMETHASONE

  • 1 January 1981
    • journal article
    • research article
    • Vol. 42  (7) , 1192-1197
Abstract
Reactivation of infectious bovine rhinotracheitis (IBR) virus in calves administered dexamethasone (DM) was studied in 2 experiments. At 2, 3, 5, 15 or 30 mo. after inoculation of the Los Angeles strain of IBR virus, i.v. injections of DM were given for 5 consecutive days to induce a recurrent infection (experiment 1). Three months after the 1st treatment, a 2nd recurrent infection was induced, using DM with the same doses as used in experiment 1. The virus was excreted from nasal secretions from the 4th-10th day after initial treatment with DM, and from the 6th-9th day after the 2nd treatment. On pathologic examination, trigeminal ganglionitis, consisting of many proliferated microglia and inflammatory cells, was observed in all DM-treated calves. Moreover, degeneration of the ganglion cells and neuronophagia were prominent features in the calves after the 2nd recurrent infection. The trigeminal ganglion may be 1 of the latent sites of IBR virus in calves after intranasal infection. Calves apparently can develop a recrudescent infection after DM treatment several times during their lifetime.

This publication has 0 references indexed in Scilit: