Breeding Cycle Dog Facts.
The Dog Breeding Heat Cycle.

This breeding cycle dog guide explains the classic dog breeding heat cycle. However, every bitch is different! And there are factors that can alter the dog heat cycle in breeding dogs…

To start off we’ll look at the lifetime reproductive cycle of the average small breed dogs. Then we’ll describe the “textbook” dog breeding heat cycle of the smaller breeds.

However, when looking at this dog breeding guide, it is important to remember that large breed dogs tend to commence cycling later in life, and also cycle less frequently than the smaller breeds.

Lifetime Breeding Cycle Dog

Small breed dogs tend to mature faster than large breeds, so the age at which dogs reach sexual maturity depends largely on their size.

Breeding in the Male Dog

As a rule of thumb males first become fertile at about six months of age. One precocious Miniature Schnauzer boy of mine, unbeknown to me at the time, got a bitch pregnant when he was only 7 months old!!!

By 12 to 15 months the male dog has reached full sexual maturity, and if healthy can remain sexually active and fertile into old age. Unlike bitches, adult males can mate at any time.

Breeding in the Female Dog

The first heat season (also called estrus) of the bitch occurs after she turns six months of age, although it might not eventuate until she is 18 months or even two years of age. Estrus is the period when the bitch is fertile and willing to be sexually receptive to a male.

Unless she is well grown and at least 12 months of age when it comes up, the bitch should not be bred during her first season.

From then on, estrus generally recurs at every six months or so until late in life. However, by the age of 7 years, more than 50% of bitches will have ceased cycling and their sexual life will be over.

Official Breeding Cycle Dog Rules

Registered breeders in Australia follow a Code of Practice that limits the number of litters bred from a bitch.

Specifically, where a bitch is capable of producing two litters a year, only two consecutive litters should be bred, followed by a rest period of a skipped litter before breeding again.

Regarding age at breeding, the AKC stipulates that (except in special circumstances) only pups born of bitches between 8 months and 12 years, and by dogs between 7 months and 12 years of age, are eligible for registration.

Active Breeding Cycle Dog

Physiological Breeding Cycle Dog

Breeding cycle dog physiology chart annual

Physiologically, the bitch’s cycle can be divided into four periods.

• Proestrus:

The bitch attracts males, has a bloody vaginal discharge, and her vulva is swollen. Proestrus lasts approximately nine days; the bitch, however, will not allow breeding at this time.

• Estrus:

During this period, which also lasts approximately nine days, the bitch will accept the male and is fertile. Ovulation usually occurs in the first 48 hours; however, this can vary greatly.

• Diestrus:

Lasting 60 to 90 days, diestrus is the period when the reproductive tract is under the control of the hormone progesterone. This occurs whether or not the bitch becomes pregnant.

False pregnancy, a condition in which the bitch shows symptoms of being pregnant although she has not conceived, is occasionally seen during diestrus.

• Anestrus:

No sexual activity takes place. Anestrus usually lasts between three and four months (but can be much longer, especially in large breed dogs).

Breeding Cycle Dog Breeding Guide

Translating the above “physiological” phases of the dog breeding heat cycle into normal language, the stages will actually look like this in real life:

• Heat – bleeding (proestrus)

Mating (estrus)

• Pregnancy (diestrus)
• Lactation (anestrus)

• Rest and recuperation (anestrus)

Breeding cycle dog annual maximum

Please note that this pie chart depicts a maximum breeding year and is not meant to imply that it is usual to maintain such frequent breeding year in and year out!

Pregnancy, and most particularly, lactation, makes heavy demands on the body of the bitch.

After two consecutive whelpings, all bitches should have an interval of at least a year before the next to recuperate. Ignore this rule and you risk your bitch developing major health problems, especially reproductive issues and dog breeding problems.