Dogs and cats that will not be used for breeding should be desexed, to prevent accidental breeding and the euthanasia of unwanted litters of puppies or kittens.
There are many health, behavioural and financial benefits of desexing your dog or cat, and you can safely desex them from 3 months of age - this is called 'early age desexing'.
If you intend to use your pet for breeding, first make sure you will be able to find homes for the litter. If you keep any animal after 12 weeks of age, you may need a permit to keep these pets on your property, see Owning multiple pets.
For more information about desexing your pet, contact your vet.