RISK-FACTORS FOR DEVELOPMENT OF CHRONIC SUPERFICIAL KERATITIS IN DOGS

Proportional hospital accession ratios for chronic superficial keratit is (CSK) of dogs were determined for 16 US veterinary teaching hospita ls participating in the Veterinary Medical Data Base between Jan 1, 19 76 and Dec 31, 1991. The prevalence of CSK was significantly correlate d (r = 0.90) with altitude of residence, but not with latitude, longit ude, mean annual solar radiation, or mean annual relative humidity. Me dical records of dogs with (n = 595) and without (n = 72,877) CSK exam ined at the Colorado State University Veterinary Teaching Hospital bet ween Jan 1, 1976 and Oct 28, 1991 were also reviewed. Belgian Tervuren , German Shepherd Dogs, Border Collies, Greyhounds, Siberian Huskies, and Australian Shepherds were disproportionately affected. Dogs betwee n 4 and 7 years old were 2.36 times more likely to develop lesions tha n were dogs < 4 years old CP < 0.05). Among dogs < 4 years old, spayed females, sexually intact males, and castrated males were more likely to develop the condition (P < 0.05) than were sexually intact females. Altitude of residence was a significant risk factor in the developmen t of csK among dogs in Colorado. Dogs living at altitudes > 7,000 ft a bove sea level were 7.75 times more likely to develop lesions than wer e dogs living at elevations between 3,000 and 5,000 ft.