To spay/neuter or not to spay/neuter

Sterilization will naturally serve to prevent any unwanted litters. In bitches, spaying will greatly reduce the risk of breast cancer, pyometra, perianal fistula and cancers of the reproductive organs.⁵

Spay surgery itself carries a somewhat high rate (around 20%) of complications such as infection, haemorrhage and even death.⁵

Spaying significantly increases the rate of urinary incontinence in bitches….about 20-30% of all spayed bitches will eventually develop this problem. This is believed to be most likely caused by the lack of oestrogen that results from being spayed.¹

Sterilization of males may reduce some unwanted sexual behaviours, but there are few other proven benefits to neutering a male dog. Testicular cancer is prevented, but the actual risk of that cancer is extremely low (<1%) among intact dogs. Contrary to popular belief, studies show that the risk of prostate cancer is actually HIGHER in neutered dogs than in their intact counterparts.⁵

Several studies prove significant health risks associated with sterilization, particularly when done at an early age. The most problematic is a delayed closure of the bony growth plates. This results in an abnormal, “weedy” skeletal development that increases the incidence of orthopaedic problems like hip dysplasia and patellar luxation. Working and performance dogs, if neutered before maturity, risk the inability to perform the jobs they were bred for.¹⁰

But by far the most startling news to surface this year is the result of a study that shows that keeping ovaries to the age of six years or later is associated with a greater than 30% increase of lifespan in female Rottweilers.⁴ Similar studies in humans reinforce this finding.^7,11

A 30% longer lifespan means that you could have many additional years with your bitch simply by delaying spay surgery until middle-age or later.

Behavioural studies show that sterilization increases fearfulness, noise phobias and aggression. Other well-documented adverse health effects of de-sexing include increased risk of bone cancer, haemangiosarcoma, hypothyroidism, and cognitive dysfunction in older pets. Sterilization confers an increased susceptibility to infectious disease, and also a higher incidence of adverse reactions to vaccines.¹⁰

“potential health problems associated with spaying and neutering have also been identified, including an increased risk of prostatic cancer in males; increased risks of bone cancer and hip dysplasia in large-breed dogs associated with sterilization before maturity; and increased incidences of obesity, diabetes, urinary tract infections, urinary incontinence, and hypothyroidism.” Ref: AVMA.org

In a study of well over a million dogs, information on breed, sex, and age was collected and reported to the Veterinary Medical Database between 1964 and 2003. Results—Castrated male dogs were significantly more likely than other dogs to have hip dysplasia (CHD) than other dogs and spayed females were significantly more likely to have cranial cruciate ligament deficiency (CCLD).

Dogs up to 4 years old were significantly more likely to have HD whereas dogs over 4 years old were significantly more likely to have CCLD. In general, large- and giant-breed dogs were more likely than other dogs to have HD, CCLD, or both.

Prevalence of HD and CCLD increased significantly over the 4 decades for which data were examined. There was no data reflecting the decade-by-decade increase but one might suspect that the significantly increased rate of spay and castration procedures may be a factor in the overall forty-year increase. ref: June 15, 2008 Journal of the American Veterinary Medical Association

“increased rate of cystitis and decreasing age at gonadectomy was associated with increased rate of urinary incontinence. Among male and female dogs with early-age gonadectomy, hip dysplasia, noise phobias, and sexual behaviours were increased, whereas obesity, separation anxiety, escaping behaviours, inappropriate elimination when frightened…”

REFERENCES AND FURTHER READING
¹ Bovsun, Mara; "Puddle Jumping; Canine Urinary Incontinence"; AKC Gazette April 2009
barkingbulletin.com/newsletter/2009/q4/Puddle-Jumping--Canine-Urinary-Incontinence/

² Fry, Mike, "Reflections from the No Kill Conference in Washington DC":
animalarkshelter.org/animal/ArkArticles.nsf/AllArticles/3A078C33CD079D17862575AD00471A9B

³ James, Susan Donaldson (ABC News) "300,000 Imported Puppies Prompt Rabies Concerns"
October 24, 2007 petpac.net/news/headlines/importedpuppies/

⁴ Nolen, R. Scott "Rottweiler Study Links Ovaries With Exceptional Longevity"
JAVMA March 2010 avma.org/onlnews/javma/mar10/100301g.asp

⁵ Sanborn, Laura J., MS
"Long-Term Health Risks and Benefits Associated with Spay/Neuter in Dogs"; May 14,2007
naiaonline.org/pdfs/longtermhealtheffectsofspayneuterindogs.pdf

⁶ Thoms, Joy "The Importance of Spay-Neuter Contracts" The Orient Express, Nov, 2009

⁷ Waters, David J., DVM, PhD, Diplomate ACVS "A Healthier Respect for Ovaries"
gpmcf.org/respectovaries.html

⁸ Winograd, Nathan J. "Debunking Pet Overpopulation" June 29, 2009
nathanwinograd.com/?p=1390

⁹ Winograd, Nathan, “Redemption: The Myth of Pet Overpopulation and the No Kill Revolution in America” Almaden Books, 2nd edition, Feb 25, 2009.

¹⁰ Zink, Christine, DVM, PhD, DACVP
"Early Spay-Neuter Considerations for the Canine Athlete"; 2005http://www.thedogplace.org/Veterinary/0603-SpayNeuter_Zink.asp

¹¹ “Retaining ovaries may be a key to prolonged life in women and dogs”; DVM Newsmagazine; Dec 5, 2009. veterinarynews.dvm360.com/dvm/ArticleStandard/Article/detail/646838