Rat Cytomegalovirus Infection

Rats are host to their own rat-specific cytomegalovirus (RCMV). Based upon presence of lesions in salivary glands, RCMV is common among wild rats, but appears to be nonexistent in laboratory rats. RCMV infects the salivary and lacrimal glands, causing cytomegaly with both intracytoplasmic and intranuclear inclusions in ductal epithelium, with nonsuppurative interstitial inflammation. Intracerebral inoculation of suckling rats with RCMV will produce nonsuppurative encepha­litis with karyomegaly, intranuclear and intracytoplas- mic inclusion bodies in neural tissue, and polykaryocyte formation. Serological tests are available but not gener­ally applied because of their rarity in laboratory rat populations.