Comparative biological characterization of mouse adenovirus strains FL and K 87 and seroprevalence in laboratory rodents

The growth, stability and seroprevalence in laboratory rodents of the two known strains of mouse adenovirus were compared. The FL strain of mouse adenovirus grew in both L 929 murine fibroblasts and in CMT-93 murine rectal carcinoma cells, whereas the K 87 strain grew only in CMT-93 cells. The bulk of the FL progeny virus was released from the host cells. K 87 virus was largely cell-associated. Both virus strains were stable at 37° C in liquid medium. The K 87 strain was completely inactivated after 5–15 minutes at 56° C, whereas FL infectivity was still detected after two hours at this temperature. Both virus strains were stable in the dessicated state for 14 days, although FL viability was more dependent on the presence of protein in the virus diluent. Seroepidemiologic data suggest that viruses antigenically related to mouse adenovirus are more prevalent among laboratory rats than among laboratory mice and that the virus(es) infecting rats differ from those infecting mice. Results of retrospective serologic testing suggest an association between mouse adenovirus and an outbreak of disease in a mouse breeding colony.