Objective—To characterize retroviruses isolated from
boid snakes with inclusion body disease (IBD).
Animals—2 boa constrictors with IBD and 1 boa
exposed to an affected snake.
Procedure—Snakes were euthanatized, and tissue
specimens and blood samples were submitted for
virus isolation. Tissue specimens were cultured with
or without commercially available viper heart cells and
examined by use of transmission electron
microscopy (TEM) for evidence of viral replication.
Reverse transcriptase activity was determined in
sucrose gradient-purified virus. Western blotting was
performed, using polyclonal antibodies against 1 of
the isolated viruses. Specificity of the rabbit anti-virus
antibody was evaluated, using an immunogold-labeling
Results—3 viruses (RV-1, RV-2, and RV-3) were isolated.
The isolates were morphologically comparable
to members of the Retroviridae family. Reverse transcriptase
activity was high in sucrose gradient fractions
that were rich in virus. Polyclonal antibody
against RV-1 reacted with proteins of similar relative
mobility in RV-1 and RV-2. By use of immunogold
labeling, this antibody also recognized virions of both
RV-1 and RV-2.
Conclusions and Clinical Relevance—A retrovirus
was isolated from boid snakes with IBD or exposed
to IBD. Western blot analysis of viral proteins indicated
that viruses isolated from the different snakes
were similar. Whether this virus represents the
causative agent of IBD is yet to be determined. The
isolation of retroviruses from boid snakes with IBD is
an important step in the process of identifying the
causative agent of this disease. (Am J Vet Res