Along with helping to prevent cat and dog overpopulation, there are many other benefits of desexing dogs and cats.

If you aren't going to breed from your cat or dog, please have him or her desexed as soon as possible, as cats and dogs can begin to breed from an early age. You are less likely to forget to desex your cat if you have it done as soon as the cat or dog is purchased or obtained.

In general, cats and dogs can be safely desexed from three months of age. Desexing at a younger age can be less stressful than it would be for older animals, and they may recover more quickly.

Desexing benefits

Population control

Animal shelters and pounds across Victoria receive thousands of animals each year, with many of them being bred by accident because their owners didn’t get around to desexing their pets.

Desexed animals cannot breed and therefore cannot add to the increasing number of strays and unwanted animals. Councils support the desexing scheme in order to promote responsible pet ownership.

Behavioural changes

Both male and female cats and dogs show significant behavioural benefits from being desexed. Desexed pets are less likely to be a problem to councils and the community than undesexed pets. Dogs and cats that are confined to their property are less likely to become lost, be hit by a car or be stolen.

Male dogs and cats

Castrated males are less likely to roam, or to urinate within the property. Castration does not always completely eliminate the sex drive or ability to copulate, but castration does stop mounting behaviour in 60% of dogs. There is a reduction in aggression toward other male dogs, and a reduction in dominance behaviour, making dogs more manageable.

The presence of testosterone slightly increases aggressive tendencies in general. The loss of that hormone also tends to reduce aggressive behaviour towards people, reducing the risks of attacks, especially on the owner’s family and other people in the community.

Female dogs and cats

In females, desexing prevents oestrous (on heat) behaviour and problems of attendant male dogs creating a public nuisance. Once behaviour problems have developed, it can take six months after desexing until behavioural improvements are seen, so desexing before unwanted traits develop is recommended.

Medical benefits of desexing

The appropriate age of desexing your pet should be determined after discussions with a veterinary practitioner.

There are significant medical advantages for both sexes:

  • Female dogs cannot develop serious uterine infections which are common in older undesexed female dogs.
  • Early desexing (before the first season) greatly reduces the risk of female dogs developing mammary cancer (breast cancer), which can be fatal.
  • Desexed male dogs are unlikely to develop the very common prostate diseases which can be fatal.
  • Desexing greatly reduces the incidence of fighting in cats and so reduces abscesses and infections including Feline Immunodeficiency Virus (FIV), which is sometimes referred to as Feline AIDS. FIV is spread by biting.
  • Reducing the tendency of both desexed dogs and cats to roam reduces the likelihood of the animal being injured or killed in road accidents.

More information on the benefits of desexing

Your vet can give you further guidance on desexing your pet.

To find out more, visit Agriculture Victoria's Desexing page.