Things to Think About Before Breeding your Dog

We find one of the most common questions asked at the clinic is “how can you tell when a dog is on heat and how long does it last?” Puberty in the female dog usually occurs around 6 months of age, with the smaller breeds having their first heats earlier then larger breeds due to reaching mature bodyweight earlier. In general dogs cycle every 6-7 months but it can vary from dog to dog. ‘On heat’ is a general term but there are actually different stages within a heat cycle which are important for the owner to be aware of to avoid accidental pregnancies.

* 1st stage – the female is attractive to other dogs but might not be receptive to breeding, some can even show aggression. Vaginal bleeding and vulva swelling is noted. The average length is 9 days

* 2nd stage – the female is more passive and receptive to male dogs for mating. The bleeding may diminish to varying degrees but vulva swelling is at a maximum. This is the most fertile period and on average lasts 9 days.

* 3rd stage – the female is disinterested in males, discharges and swellings decrease. This stage lasts 2-3 months in the abscess of pregnancy. Towards the end non pregnant females can develop mammary enlargement and milk production.


Females have the ability to conceive if mated during the 1st and 2nd stage as the dog semen can last 9 days in the female. This means if the female is bred even before the most fertile period it can still result in pregnancy. It is important to note that even if the dogs have not been found “tied” or “knotted” it is still possible for the female to fall pregnant. If dogs are “knotted” there is no point in separating them as the damage has already been done. A castrated male also has the ability to serve a female for 6 weeks post surgery.


If a mismating has occurred or you want to avoid your dog coming into season there are options available to avoid unwanted pregnancies. Please call Gunnedah Veterinary Hospital on 67421834 to discuss.