Abstract

Lumbosacral disease is not commonly described in rodents and was diagnosed in a 13-year-old capybara (Hydrochoerus hydrochaeris). The animal presented with a persistent penile prolapse unresponsive to chemical castration, hindlimb lameness, progressive ataxia, and a loss of bladder control. Its clinical condition had progressively worsened over multiple years with only marginal improvement on various treatments, and a decision was made to euthanize the animal. Computed tomography was performed postmortem to evaluate the utility of this diagnostic tool in this species and to have a baseline for comparison in the future for its conspecific of a similar age. The imaging study revealed degenerative changes of the lumbosacral spine with instability of the L6–S1 disc space and likely impingement of the spinal nerve roots as a result of mineral foci in the intervertebral foramina. The necropsy confirmed the presence of a severe, chronic degenerative intervertebral disc disease at the lumbosacral junction with ankylosing spondylosis, consistent with the diagnosis of lumbosacral disease seen in other mammals. In summary, large rodents appear susceptible to the same degenerative articular changes in the spine as domestic mammals, and lumbosacral disease should be included in the list of differential diagnoses of large rodents presenting with similar clinical signs of neurologic impairment.