In search of a strategic disturbance: some thoughts on the timing of spaying

The aim of this paper is to provoke a thoughtful re-evaluation of our assumptions regarding the health consequences of elective ovariohysterectomy in pet dogs. It proposes that we might re-shape our thinking about the physiological impact of the timing of spaying and commit ourselves to making spaying a strategic physiological disturbance. Several observations that may help to guide this re-shaping are offered. First, the scholarly manuscripts of the veterinary profession routinely describe study populations in terms of male versus female, as well as neuter status. This implies that sex differences in biology can lead to clinically significant differences between males and females, and that gonad removal might re-set the system in important ways. Taken together, this suggests that the concept of ovary removal as a physiological disturbance, although not talked about, is already deeply rooted in the minds of veterinarians. Second, we have an incomplete understanding of the association between the diagnosis of mammary cancer or pyometra and the life expectancy of female dogs. This lack of data regarding the impact that these two health hazards of ovary retention exert on overall longevity points to a high research priority. Further, a more rigorous evaluation of the impact that the timing of spaying has on health will require investigators to revise their vocabulary, replacing the categories “spayed” or “intact” with measures of actual lifetime ovary exposure. Finally, we might do well to mimic the mindset of scientists in the field of evolutionary developmental biology who know that timing is everything when it comes to discovering what strategic disturbances can nudge a biological process closer to an intended outcome. Optimistically, the author posits that on the horizon sits a new set of research questions that will drive a revised conception about what we should want to know about the timing of spaying and health.