Spay and Neuter Surgeries

Spay surgeries, otherwise known as ovariohysterectomies are the removal of the ovaries and uterus in dogs and cats. 

Not only does spaying help eliminate unwanted pregnancies, but it also decreases the risk of many diseases and problematic behaviours.  We do see these diseases with non-spayed dogs and cats often.  They are not at all rare. 


Spayed dogs before the first heat have a 0% chance of developing mammary cancer (breast cancer).  Once they have a heat (period), the risk increases to 7% chance, and if they have more than 2 heat cycles, 1 in 4 unspayed female dogs will develop mammary cancer.    

It is not too late to spay the dog if she has had heats.   Dogs who develop tumours are immediately spayed.  Mammary tumours are created by estrogen produced by the ovaries.  Once the ovaries are removed, the spread of the disease is minimized. 

Pyometra is caused when the uterus becomes infected.  The hormones released into the body when a dog experiences a heat cause the uterus to swell and relax allowing bacteria to enter easily.   It will literally fill with pus and blood.   This is always an emergency immediate surgery.  It can be fatal – even with surgery.   The surgery is a spay.  The infected uterus must be removed.  It is not an easy spay, as the entire reproductive tract is often inflamed, contains more blood supply, and is very friable and can tear or break with even gentle manipulation.



Cats are more at risk of developing mammary cancer than dogs.  The more heat cycles the cat has had, the more risk of the cat developing mammary cancer at some point in its life.   Mammary cancer in cats can be incredibly aggressive and often will spread to the lungs causing respiratory issues and ultimately respiration failure and death.  Spaying a cat early will help eliminate this risk. 

Cats are also susceptible to pyometra.   This occurs when the uterus swells during the heat and becomes susceptible to infection, and fills with pus and blood.   When this occurs, an emergency life-saving spay surgery to remove the infection is required.

Cats are induced ovulators and can go in and out of heat repeatedly.  Some of the behavioural issues with a cat in heat are not desirable.   Many people lose sleep due to the yowling and posturing of the cat.   Cats can actually urinate inappropriately during this time.  This is caused by some hormonal influence, or may be due to some abdominal pain and cramping. 


Also very important, the cat overpopulation issue is a major concern in Ottawa.  Feral and stray cat colonies exist all over the city and many different rescue organizations, in addition to the Ottawa Humane Society have been working on Trap-Neutering and Return programs.   There are so many unwanted kittens and cats that spaying is a responsible thing to have done. 



Both dogs and cats can become aggressive and territorial when they are not neutered.  Both species can urine mark items inside and outside of the home.  In addition, they both have a tendency to want to roam and mate. 


Non-neutered dogs can develop a variety of prostate diseases.  Some of these are abscesses, or infection, but the most serious is the enlargement of the gland.   The longer the prostate gland is under the influence of testosterone, the more it will grow. It can enlarge so much that the dog may develop difficulty having bowel movement or make urination uncomfortable. 

Male dogs can develop testicular tumours.  Some of these cancerns are benign, and a neuter surgery to remove the testes is all that is required, but there are some testicular tumours that will cause metastatic disease and spread to the lungs of the dog. 


Some dogs who are not neutered or at an increased risk of perineal hernias.  These are very problematic as it is a weakness in the abdominal wall, and intestines, fat, or sometimes even the bladder can become trapped into this area.   Surgery is required but there is always an increased risk of it reoccurring. 


There are studies that if you neuter your male cat, he will decrease roaming, fighting and spraying by 90%.   If he is neutered early in life before he develops these behaviours, he will be unlikely to develop any of these behaviours. 


Again, some of the same diseases are still seen in unneutered male cats as seen in dogs.   Cats can develop both testicular and mammary cancers related to the high levels and length of testosterone exposure. 

Cats can also have urination difficulties from an enlarged prostate gland.


Neutering a male cat will subdue the smell of cat urine. 


Regardless of the type of surgery, or the complexity of it, we always discuss it with you in detail.

For surgeries, our patients are placed under a general anesthesia and we take all the precautions we can to provide a safe and well managed anesthesia and hospital stay.   We have monitoring equipment and a veterinary technician who looks after them from the moment they arrive, until they leave to go home with you.  We have warming devices, soft blankets and pillows.    All patients are placed on intravenous fluids for their procedures to minimize anesthesia risk, improve blood pressure, and help flush out the medications and anesthesia for a speedy recovery.