Most assuredly, dog overpopulation is a serious problem in the United States. No one needs me to tell them that millions of our loyal canine friends are put to death every year, mostly as a result of there simply being too many of them. There is no question that spay/neuter programs have dramatically reduced this problem, but efforts to encourage dog owners to alter their animals have generated an increased misrepresentation of the facts regarding the matter. Some facts are exaggerated while others are intentionally -or not- obscured, and this certainly inhibits the ability of the average dog owner to make an informed decision about what is best for his/her pet.
Those urging the sexual alteration of pets will often list a plethora of health and behavioral benefits for doing so, but will seldom provide scientific reference to support it. In addition, the risks associated with such procedures frequently go unmentioned, or are downplayed. So I will attempt here to provide some real objective facts relating to the spaying and neutering of dogs, based on various health and behavioral studies, several of which I will list within this post.
First, the actual health benefits resulting from the neutering of male dogs:1) The most obvious benefit of neutering a male dog is the complete elimination of testicular cancer. Death from this affliction occurs in about 0.9-1% of intact male dogs.
2) Neutering does appear to minimize the risk of developing non-cancerous prostate problems.
3) Neutering apparently reduces the risk of perianal fistulas (infectious lesions around the anus).
Risks associated with neutering male dogs:1) Neutering a dog greatly increases its risk (0.2% of intact dogs) of developing bone cancer. This is especially true if a dog is neutered before 1 year of age.
2) Neutering increases the risk of Cardiac Hemangiosarcoma (tumors of blood vessel cells in the heart, which affects about 0.2% of intact dogs) by 160%.
3) Neutering doubles the risk of urinary tract cancer (affects approximately 1% of intact males).
4) Triples the risk of hypothyroidism (affects less than 1% of intact dogs) and obesity (affects about 2.8% of intact dogs).
5) Quadruples the risk of prostate cancer, which affects 0.2-0.6% of intact males.
6) Increases the risk of progressive cognitive impairment in older dogs.
7) Increases the risk of bone and joint disorders.
8) Increases the likelihood of adverse reactions to vaccinations.
Health related benefits of spaying a female dog:1) As in males, reduces the risk of developing perianal fistulas.
2) Eliminates the risk of cervical, uterine, and ovarian cancers, which affect approximately o.5 % of intact females.
3) Minimizes the risk of Pyometra, a serious infection of the uterus which affects around 23% of intact female dogs, and kills about 1%.
4) Dramatically reduces the risk of mammarian cancer if procedure is performed before 2 1/2 years of age. Mammarian tumors affect about 3.4% of intact females, and accounts for about 52% of all cancers in female dogs.
Risks associated with spaying female dogs:1) As in males, greatly increases the low 0.2% risk of bone cancer if done before 1 year of age.
2) Doubles the risk of urinary tract cancer, which affects less than 1% of intact females.
3) Nearly triples the likelihood of obesity (affects about 2.8% of intact dogs).
4) Nearly quadruples the risk of recurrent or persistent urinary tract infections.
5) Increases the risk of Cardiac Hemangiosarcoma (affects about o.2% of intact dogs) by about 500%.
6) More than triples the risk of Splenic Hemangiosarcoma (blood vessel cell tumors in the spleen affecting less than 0.2% of intact dogs).
7) Results in urinary incontinence in as many as 20% of females.
8) Triples the risk of hypothyroidism (affects less than 1% of intact dogs).
9) Increases the risk of recessed vulva and vaginal inflammation, particulary if procedure is performed before puberty (generally 6 months to a year old).
10) As in males, increases the risk of bone and joint disorders, as well as the risk of adverse reactions to vaccinations.
Behavioral effects resulting from spay/neuter of dogs:Studies conducted by those such as J.C. Neilson and colleagues, F.A. Beach, O'Farrell and Peachey, Voith and Borchelt, Hopkins and colleagues, Ben Hart, Kreutz, and so many other brilliant minds have varied somewhat in their conclusions, but the general results
have given us a very good idea of what one should or shouldn't expect regarding behavior after spaying or neutering a dog.
Potential behavioral effects of neutering a male:1) Reduced roaming in a very large percentage (up to 90%) of dogs.
2) Reduced mounting of people in around 50-60% of dogs.
3) Reduced urinary marking indoors in about half of dogs.
4) Reduced intermale aggression in up to 60% of dogs.
5) Studies also indicate that general dominance aggression, particularly toward people,
may be curbed in some dogs. Neutering seems to have little to no effect on territorial, protective, or fear aggression.
Please note that behaviors tend to be
reduced, as opposed to entirely eliminated.
Spaying of females seems to have basically no influence on behavior. The primary exception is that in some females, especially those who exhibit aggressive tendencies before being altered, aggression is often increased after being spayed.
The facts presented here are the results of extensive scientific study. I've refrained from interjecting any personal opinions I may have on this matter for the sake of objectivity.
Hopefully I've provided enough information for dog owners to be a little better equipped to deal with the decision to spay or neuter their pets.
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