Τhe spaying of a female cat or dog is an abdominal surgery which involves the removal of both the ovaries and uterus. There are a number of reasons as to why you should spay your pet, the most important of which are listed below:
Over 25% of non-spayed female dogs will develop breast or mammary tumours. Spaying pets can protect them, depending on the timing. The risk of a dog having mammary tumours is 0.05% if a female is spayed before their first heat. It then increases to an 8% risk after their first heat, and 26% after their second heat. If a dog is spayed after 2 years of age then there is no less risk of developing breast cancer. However, it will protect her against other conditions, including pyometra (see below). This is the reason why we typically recommend spaying before the 1st or 2nd heat cycle, depending on the breed. In dogs, approximately 50% of mammary tumours are benign and 50% are cancerous. In cats, 90% of mammary tumours are cancerous, so spaying is even more important.
Pyometra is a serious condition where the uterus fills with pus. It is common in non-spayed dogs and unusual in cats. In turn, pyometra can affect many organs, which can make a pet very sick or even kill her. One of the organs that classically gets damaged is the kidney. Sometimes the uterus may rupture which leads to pus collecting inside the belly (septic peritonitis). Pyometra is treated by surgical removal of the uterus and ovaries, long antibiotic treatment and possible hospitalisation depending on the patient's status.
Letting a non-spayed cat or dog roam is similar to gambling. Now not only do you have to deal with the pregnancy, but in 2 months, you will need to make sure that the delivery goes well. Then you will have to keep the 1, 2, 3… or 10 babies or find them a new home. Multiply that by one or ten or one hundred thousand, and you start to understand the complex problem of pet overpopulation. This leads to millions of abandoned or euthanised pets.
Sometimes, natural delivery just isn’t possible for health or anatomical reasons. Bulldogs, Chihuahuas and Yorkshire Terriers are some of the breeds with an increased risk of needing a C-section.
As a general rule, most females have their first heat cycle around 6 months of age. A heat cycle causes mood swings, swollen nipples, attraction of males, a swollen vulva and a bloody discharge. It can be quite stressful for everybody involved.
Sure, diseases of the ovary, such as tumours, are rare. But a real good way of eliminating that risk is to spay a patient.
Likewise, tumours of the uterus are not common, but spaying eliminates this risk.
False pregnancy is a strange and stressful condition where a pet is convinced that she’s pregnant… when she’s not! Females show nesting behaviour (i.e. they literally make a nest for her imaginary offspring), their belly gets bigger, and they produce milk. Spaying can eliminate the possibility of this condition.