[Attenuated rabies virus, ERA strain, in cattle and dogs vaccinated with multiple doses]. / Recherche sur le virus attenue de la rage, souche ERA, chez des bovins et des chiens vaccines avec des doses multiples.

Investigation on the vaccination of 18 cattle and 5 dogs against rabies is reported. Each animal received multiple doses of ERA strain vaccine intramuscularly in the gluteal or masseter region. The saliva, the brain and salivary glands of the vaccinated animals were examined to detect the presence of ERA virus using immunofluorescent test and mouse inoculation. The virus was never found in the saliva and organs of treated animals. Circulating antibodies against ERA rabies virus were detected in all vaccinated cattle and dogs.

Clinical and anatomo-histopathological features of experimental infection by DF-2 in rabbits.

Clinical and anatomo-histopathological features of experimental infection by DF-2 in rabbits are described. Hyperthermy, sensory reduction, diarrhoea, weight loss and catarrhal nasal discharge are reported. PTT and PT are shown to increase and number of platelets diminish markedly. Considerable haemorrhagic diathesis is reported for several organs. Several clots (especially in pulmonary vessels), serious alterations in kidney glomeruli, degeneration of hepatocytes and disseminated necrosis foci are also reported. Lesions are stated as being very similar to those observed in man.

Evaluation of the experimental pathogenicity of some Cryptococcus species in normal and cyclophosphamide-immunodepressed mice.

The pathogenic potential of distinct Cryptococcus species has been evaluated in mice rendered leukopenic by one or two injections of the potent immunosuppressive drug cyclophosphamide (Cy). Pathogenicity assessment included enumeration of viable cryptococcal cells in animal organs and histopathological observations. It was found that putatively non-pathogenic species of Cryptococcus, in particular C. cereanus and C. albidus, showed significant lethality for Cy-treated mice. In Cy-immunodepressed mice, challenged with the infectious cryptococcal cells two days after pharmacological treatment, a significant decrease of LD50 (equivalent to at least one order of magnitude) was observed for all Cryptococcus species. However, the pathogenicity enhancement due to Cy immunodepression was greater with C. neoformans. In all cases, brain and kidney were the most invaded tissues as also evidenced by histopathological examination, which showed the typical cystic lesion. All the observations made point to the conclusion that the pathogenic potential, for the immunomodulated host, of Cryptococci other than C. neoformans is significant being quantitatively and not qualitatively different from that of C. neoformans, as evidenced by a similar organotropism and similar type of histological lesions in the target organs (brain and kidney).