Multifocal serous chorioretinitis in beagle dogs

In the years 1988 and 1989, routine ophthalmological examinations of dogs from the company-owned beagle colony revealed a clinically inapparent chorioretinitis in 7.4 and 10% of the animals, respectively, as it has previously been described by Weisse et al. (1981). The alterations were seen mainly in the non-tapetal fundus, and they appeared more frequently in both eyes than in just one eye. Infection tests as well as virologic, bacteriologic and histopathologic investigations were performed in order to clarify the origin. A direct evidence of virus particles from processed ocular material by electron microscopy was not possible. Tests for growth on MDCK cells were negative. In bacteriologic tests, a gram positive, filiform, branched microorganism was isolated. The histopathologic findings in the subacute stage were a focal atrophy of the first retinal neuron and a focal proliferation of glia cells.