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The importance of desexing

Why desex?

For many dogs and cats there are a number of very good reasons why it is important to consider desexing (an often surgical procedure to stop the reproductive tract from working, usually by having part of the reproductive tract removed). Further to this, there are several factors to take into consideration when electing the most suitable age for your pet to be desexed.

First and foremost, desexing is used as an invaluable tool to help combat pet overpopulation, which is a huge animal welfare issue worldwide. The massive number of animals that are abandoned, aren’t adequately cared for or can’t be rehomed leads to millions of dogs and cats being euthanised each year.

Except in very tractable and well-behaved animals, dogs and cats (especially males) that have not been desexed tend to be driven by their sexual hormones. They roam to seek mates, have aggressive behaviour when defending their territory, and urinate frequently to mark their territory. If the animal’s need to express sexual behaviour is not met then it often escalates to destructive behaviour. These behaviours are not only largely unacceptable in our society, but they often lead to injury of the individual, other animals and sometimes humans, too.

Further medical considerations for desexing are mammary cancer, uterine infections, prostatic disease and hormonal imbalances. Although they have multifactorial origins, a desexed animal has a much lesser risk of developing these conditions.

Why not?

All of these factors make a good case to support the desexing of cats and dogs, especially those living in an urban environment and in close confines. But what are the negative points about desexing?

Dogs usually attain puberty at 7-12 months and cats at 4-9 months of age. At this point, there is a greater production of sex hormones which are involved with growth and development, helping to promote the maturation of cartilage and assist with calcium deposition in bones. There is concern about some of the long-term health risks of removing the benefits of these hormones.

Research has indicated that a desexed female dog is eight times more likely to suffer from urinary incontinence, and it has also been suggested that prepubertal desexing of dogs causes an increased incidence of hip dysplasia and bladder infections. Cats are more inclined to be shy and obese.

Desexing is a relatively straightforward procedure and our modern anaesthetics are generally very safe, but complications such as excessive blood loss, infection and drug reactions do occasionally arise.

What’s the best age to desex?

In prepubertal animals, the procedure is generally quicker, easier and less stressful, and there is generally a faster recovery.

Females that are on heat have a much greater blood supply to their uterus which makes surgery riskier. Therefore, it is ideal to do the surgery before they come on heat. If it’s too late then most vets prefer to wait until at least one week after the heat.

Factors outlined above need to be considered and the best age to desex is often an individual specific decision that needs to be made considering the individual, the pet population as a whole, and the needs of the client.

What’s involved?

The most commonly used approach to desex pets is the surgical removal of their reproductive organs under anaesthetic. In males, it is often referred to as neutering and in females spaying. In female animals, we make an incision into their abdomens just below their umbilicus (belly button) and then use surgical instruments such as a “spey hook” to help us locate the uterus and ovaries. There are blood vessels that need to be carefully ligated to ensure there is no severe blood loss and then the organ is removed and the incision sutured in layers to close the abdominal wall, the subcutaneous tissue (under the skin) and finally the skin layer. Some vets don’t use skin sutures as the underlying layers hold the skin together.

In male animals, the testicles are removed. This is generally less invasive and more straightforward than surgery for female animals as the testicles are outside the body cavity. However, some males are born with their testicles not yet descended into the scrotum — they are known as cryptorchids. In the developing foetus, the testicles migrate from a similar position to ovaries in a female. This process is usually complete at 2 months of age but can be delayed until 6 months. If the testicle stays in this abnormal position, either in the abdomen or in the groin, it is very likely to become cancerous so neutering is even more important.

For male animals, there is also the option of vasectomy where the vas deferens, the duct that carries sperm, is cut and sealed to make them sterile. This surgery is rarely performed as it will not reduce hormone driven behaviour.

There are other ways to make animals infertile such as chemical castration in male animals and medications that stop the production of sex hormones. Some of these are short acting and can be useful in certain situations — such as breeding animals that need to be prevented from reproducing for a period of time — but they do have risks, such as a higher likelihood of uterine infections in female animals, and these need to be carefully considered with your vet.

Responsible breeding

Breeding dogs and cats can be incredibly rewarding but it can also be an agonising process involving much heartache when things go wrong. Most pregnancies and deliveries proceed normally, but sometimes emergency veterinary intervention is necessary to save the lives of the mother, the babies or both.

Deciding to breed your dog or cat is a big decision, and places a lot of responsibility on you. Also, when deciding whether or not to breed your pet, it is important to plan ahead financially. You’ll need to set aside funds for health checks, as well as for any unexpected emergencies.

Complications such as the need for an emergency caesarian section can be very costly, so it’s best to plan ahead and to be prepared for the unexpected!

For the pet population as a whole, it is clear that desexing at a young age is an important practice that is adopted by animal shelters globally. When considering desexing your pet and the many factors relating to their specific needs as individuals, it is important to obtain guidance from your vet to help you make the appropriate decision for their long-term health.

Dr Liza

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