The Oncoming Controversy About Pet Reproductive Organs

For decades, having your pet spayed (in the female, traditionally the removal of ovaries and uterus) or neutered (in the male, removal of testes – “castration”), has been a medical and political act of faith for the average pet owner. Both animal health benefits, including animal behavioral health benefits, and sociological benefits were the basis on which to convince, cajole and sometimes shame, pet owners into making sure their animals could never reproduce. Activists, veterinarians, politicians and many ordinary citizens were all involved in encouraging universal pet sterilization

In recent decades, and accelerated by the media's interest in animal issues, there had been a rising awareness of how human irresponsibility leads to large shelter populations and unacceptable euthanasia statistics. This fed the modern movement to prevent unwanted and unintended animal reproduction, which continues today. Universal surgical sterilization was the means by which reduction in shelter euthanasia was to be accomplished. No more “accidental” litters was the goal. To a large extent in the northeastern states this has worked, but other regions of the country have not been as successful in purposefully reducing shelter populations, euthanasia and the human irresponsibility that leads to both.

What is different now is two fold. First, animal shelter populations and euthanasia statistics are no longer uniformly high across the nation, with some states having solved their prior problems, though a sizable number have not. The successful states no longer have the same urgency in advocating for universal sterilization as they did before.

Second, new medical information is gradually revealing that spay/neuter may not uniformly confer the previously attributed health benefits, and indeed in some cases may be detrimental to health and even lifespan. Previously, health benefits including reduction in certain forms of cancer and infections were incontestably attributed to sterilization surgery. However in new research, the putative benefits are not as clear cut, especially in the female.

Thus whether to sterilize, the right age at which to sterilize, and by what technique to sterilize, are being called into question in various ways by this new research and by those interested in maintaining the ability of their animals to reproduce. There is no one right answer any more, and the sociological benefits do not necessarily outweigh the possibility that allowing your individual female dog to remain intact, may actually lengthen her expected lifespan.

Dr. David Waters of Purdue University School of Veterinary Medicine has completed research which shows increased lifespan in female Rottweillers spayed late in life or not at all. His research implies, and he suspects, that the persistent presence of the endocrine organ we call the “ovary”, confers an overall benefit that affects longevity in a positive way. That idea, if proven accurate and broadly applicable across the many dog breeds will represent a paradigm shift in how veterinarians and the public will come to view universal sterilization. The jury remains out on this issue, but watch for more research, more information and more controversy as newer research results emerge.

For more information, browse the links below:

(Special thanks to my colleague, Dr. Marty Greer of Fond du Lac, Wisconsin, for her compilation of references that inform this post.)

Click here for information on Dr. David Water's Old Gray Muzzle Tour, the tour that investigated the link of lifetime ovary exposure (age of spaying/not spaying) with longevity in the dog:http://www.gpmcf.org/PressReleases/20100309PRPPROGM.pdf

Click here for the fascinating new TedX presentation by Dr. David Waters, on the last night of his Old Gray Muzzle Tour:  http://www.youtube.com/watch?v=XS9fiDn4Qo8.   

Click here for the article Dr. David Water's published in The Aging Cell, regarding the findings on Lifetime Ovary Exposure:http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2805875/

Click here to read comparable information about humans, in a nurse's study in Great Britain:  http://www.ncbi.nlm.nih.gov/pubmed/19384117

Click here for the National Animal Interest Alliance comprehensive article on the benefits and risks of spaying and neutering: http://www.naiaonline.org/pdfs/LongTermHealthEffectsOfSpayNeuterInDogs.pdf

Click here for Neutering Dogs: Effects on Joint Disorders and Cancers in Golden Retrievers: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0055937

Click here for information on removing the ovaries only versus removing the ovaries and uterus at a spay:http://www.intermountainvet.com/news/downloads/20004.pdf

Click here to read Dr. Nancy Kay of Speaking for Spot's perspective on Ovariectomy versus Ovariohysterectomy:http://speakingforspot.com/blog/?s=ovariectomy

Click here to read Dr. Margaret Root Kustritz's paper about "Determining the optimal age for gonadectomy of dogs and cats": http://www.imom.org/spay-neuter/pdf/kustritz.pdf 

Click here to read the Society for Theriogenology's position:  http://therio.org/displaycommon.cfm?an=1&subarticlenbr=323

Click here for Dr. Christine Zink's article about behavioral aspects of spaying and neutering - this one may surprise you!: http://www.vizslacanada.ca/SNBehaviorBoneDataSnapShot.pdf

Click here for Dr. Christine Zink's article about early spay and neuter considerations for the canine athlete: http://www.caninesports.com/uploads/1/5/3/1/15319800/spay_neuter_considerations_2013.pdf

Click here for the Veterinary Perspective by Alice Villalobos, "Is Early Neutering Hurting Pets?": http://www.veterinarypracticenews.com/vet-practice-news-columns/bond-beyond/is-early-neutering-hurting-pets.aspx

See this article about Dr. Iris Reichler's research on spaying and neutering - the European perspective: http://www.ivis.org/proceedings/iscfr/2008/session2/2.pdf?LA=1