Objective—To determine whether breed, age, sex, or
reproductive status (ie, neutered versus sexually
intact) was associated with the apparent increase in
prevalence of calcium oxalate (CaOx) uroliths and the
decrease in prevalence of magnesium ammonium
phosphate (MAP) uroliths in cats over time.
Animals—Case cats consisted of cats with CaOx (n
= 7,895) or MAP (7,334) uroliths evaluated at the
Minnesota Urolith Center between 1981 and 1997.
Control cats consisted of cats without urinary tract
disease admitted to veterinary teaching hospitals in
the United States and Canada during the same period
Procedure—Univariate and multivariate logistic
regression were performed.
Results—British Shorthair, Exotic Shorthair, Foreign
Shorthair, Havana Brown, Himalayan, Persian,
Ragdoll, and Scottish Fold cats had an increased risk
of developing CaOx uroliths, as did male cats and
neutered cats. Chartreux, domestic shorthair, Foreign
Shorthair, Himalayan, Oriental Shorthair, and Ragdoll
cats had an increased risk of developing MAP
uroliths, as did female cats and neutered cats. Cats
with CaOx uroliths were significantly older than cats
with MAP uroliths.
Conclusions and Clinical Relevance—Results suggest
that changes in breed, age, sex, or reproductive
status did not contribute to the apparent reciprocal
relationship between prevalences of CaOx and MAP
uroliths in cats during a 17-year period. However, cats
of particular breeds, ages, sex, and reproductive status
had an increased risk of developing CaOx and
MAP uroliths. (J Am Vet Med Assoc 2000;217:520–525)