Assessment of Stress Levels Among Cats in Four Animal Shelters

Objective: To measure stress levels among cats in traditional and enriched shelter environments via behavioral assessment and urine cortisol-to-creatinine ratios.

Design: Cross-sectional observational study.

Animals: 120 cats in 4 Boston-area animal shelters.

Procedure: Cats were randomly selected and observed during 3 periods (morning, midday, and afternoon) of 1 day and scored by use of a behavioral assessment scale. The next day, urine samples were collected for analysis of the urine cortisol-to-creatinine ratio. Information about each cat's background before entering the shelter was collected.

Results: Stress scores were highest in the morning. The relationships between the amount of time cats spent in the shelter and the cat stress score or urine cortisol-to-creatinine ratio were not strong. There was no correlation between the cat stress score and urine cortisol-to-creatinine ratio. Urine cortisol-to-creatinine ratios did correlate with signs of systemic disease and were significantly lower in cats in the more environmentally enriched shelters, compared with cats in the traditional shelters. Urine cortisol-to-creatinine ratio was highest among cats with high exposure to dogs. Of the cats in the study, 25% had subclinical hematuria detectable on a urine dipstick.

Conclusions And Clinical Relevance: In this study, the cat stress score was not a useful instrument for measuring stress because it failed to identify cats with feigned sleep and high stress levels. Urine cortisol-to-creatinine ratios can be monitored to noninvasively assess stress levels in confined cats. Environmental enrichment strategies may help improve the welfare of cats in animal shelters.