Rectal prolapse is a common clinical problem in laboratory mice. This condition may occur spontaneously, develop after genetic manipulations, result from
infections with pathogens such as Citrobacter species, or arise secondary to experimental design such as
colitis models. The current standard of care at our institution is limited to monitoring mice until tissue becomes ulcerated or necrotic; this strategy often leads to premature
euthanasia of valuable animals prior to the study endpoint. Surgical correction of
rectal prolapse is performed routinely and with minimal complications in larger species by using manual reduction with placement of a pursestring
suture. In this report, we investigated whether the use of a pursestring
suture was an effective treatment for mice with
rectal prolapse. The procedure includes anesthetizing mice with
isoflurane, manually reducing prolapsed tissue, and placing a pursestring
suture of 4-0
polydioxanone. We have performed this procedure successfully in 12 mice. Complications included self-
trauma,
fecal impaction due to lack of defecation, and mutilation of the surgical site by cage mates. Singly housing mice for 7 d postoperatively, applying multimodal
analgesia, and releasing the pursestring when indicated eliminated these complications. The surgical repair of
rectal prolapses in mice is a minimally invasive procedure that resolves the clinical symptoms of affected animals and reduces the number of mice that are euthanized prematurely prior to the study endpoint.