Can you briefly summarize your research findings?

Our results support the notion that how long females keep their ovaries influences how long they live.

The recent study by our research group published in Aging Cell reveals shortened longevity as a possible complication associated with ovary removal in dogs¹. This work represents the first investigation testing the strength of association between lifetime duration of ovary exposure and exceptional longevity in mammals. To accomplish this, we constructed lifetime medical histories for two cohorts of Rottweiler dogs living in 29 states and Canada: Exceptional Longevity Cohort = a group of exceptionally long-lived dogs that lived at least 13 years; and Usual Longevity Cohort = a comparison group of dogs that lived 8.0 to 10.8 years (average age at death for Rottweilers is 9.4 years). A female survival advantage in humans is well-documented; women are 4 times more likely than men to reach 100. We found that, like women, female Rottweilers were more likely than males to achieve exceptional longevity (Odds Ratio, 95% confidence interval = 2.0, 1.2 – 3.3; p = .006). However, removal of ovaries during the first 4 years of life erased the female survival advantage. In females, this strong positive association between ovaries and longevity persisted in multivariate analysis that considered other factors, such as height, adult body weight, and mother with exceptional longevity.

In summary, we found female Rottweilers who kept their ovaries for at least 6 years were 4.6 times more likely to reach exceptional longevity (i.e. live >30 % longer than average) than dogs with the shortest ovary exposure.

1. Waters DJ, Kengeri SS, Clever B, et al: "Exploring the mechanisms of sex differences in longevity: lifetime ovary exposure and exceptional longevity in dogs." Aging Cell on-line access October 26, 2009. CLICK HERE for link to Free PDF of Full-Length Article