Current composition and breed distribution of canine urinary stones

5706 canine urinary stones were analyzed by means of infrared spectroscopy from 1984-1996. The stones were sent in together with epidemiologic data (breed, age, sex, localisation of the stones, type of stone removal, stone frequency etc.) by more than 800 veterinarians from Germany, the Netherlands, Austria, and Switzerland. Irrespective of stone type, urinary stones were observed in almost all breeds, but small breeds like dachshound, poodle, terrier, schnauzer, and pekingese have a higher tendency to form stones. With 59.5% struvite is the most frequent stone type, followed by cystine with 15.5%. Cystine stones are becoming less frequent during the observation time, whereas the share of calcium oxalate (14.2%) and ammonium urate (6.0%) stones remains unchanged. The latter stone types are found predominantly in specific breeds. The stone formation appears predominantly at the age of 7. Male dogs form stones twice as often as female dogs. 98% of the stones were located in the lower urinary tract. About 90% of the urinary stones required surgical treatment.