Abstract:
The sustainability of captive cheetah populations is limited by high mortality due to chronic
renal disease. This necropsy study, conducted on 243 captive cheetahs from one institution,
investigated the relationships between focal palatine erosions, gastritis, enterocolitis, glomerulosclerosis,
chronic renal infarcts, renal cortical and medullary fibrosis, and renal medullary
amyloidosis at death. Associations between the individual renal lesions and death due
to chronic renal disease and comparisons of lesion prevalence between captive bred and
wild born and between normal and king coated cheetahs were also assessed. All lesions
were significantly positively correlated with age at death. Renal medullary fibrosis was the
only lesion associated with the likelihood of death being due to chronic renal disease, and
cheetahs with this lesion were younger, on average, than cheetahs with other renal lesions.
Alimentary tract lesions were not associated with amyloidosis. All lesions, except for palatine
erosions, were more common in wild born than in captive bred cheetahs; the former
were older at death than the latter. Having a king coat had no clear effect on disease prevalence.
These results suggest that age and renal medullary fibrosis are the primary factors
influencing the pathogenesis of chronic renal disease in captive cheetahs. Apart from amyloidosis,
these findings are analogous to those described in chronic renal disease in domestic
cats, which is postulated to result primarily from repetitive hypoxic injury of renal tubules,
mediated by age and stress. Cheetahs may be particularly susceptible to acute renal tubular
injury due to their propensity for stress and their extended life span in captivity, as well as
their adaptation for fecundity (rather than longevity) and adrenaline-mediated high speed prey chases. The presence of chronic renal disease in subadult cheetahs suggests that prevention,
identification and mitigation of stress are critical to the successful prevention of
chronic renal disease in captive cheetahs.
