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.

Gender and ethnic differences in urinary stress hormones: the population-based Chicago Health, Aging, and Social Relations Study.

Gender and ethnic disparities in cardiovascular disease and mortality have spurred interest in the epidemiology of stress hormone production. Greater disease burden among men and blacks raises the possibility of gender and ethnic differences in stress hormone production. The purpose of this study was to determine whether urinary stress hormones were higher among men and blacks in a population-based sample. Urinary hormone analysis permits a time-integrated assessment of the stress response system. However, differences in collection and standardization strategies have led to inconsistent findings. Subjects were an ethnically diverse population-based sample of 229 men and women aged 50-67 yr who provided an overnight urine specimen. Urine concentration was standardized using a traditional creatinine-based approach as well as a new method that accounts for muscle mass. With the use of creatinine standardization, no gender or ethnic differences were noted in epinephrine or cortisol production. Norepinephrine levels were higher among women compared with men (P = 0.001), however. After accounting for muscle mass, we found that both epinephrine (P = 0.018) and norepinephrine (P = 0.033) levels were higher among men compared with women. No significant differences in cortisol production were found by gender or ethnicity. The consistency of these results with previous studies of 24-h urine samples suggests muscle mass should be accounted for when comparing overnight urinary hormone values across gender and ethnicity.