Canine estrous cycle and breeding management

Dogs have been companions of humans for tens of thousands of years, evolving from wild wolves to the best friends we love today. A pre-breeding examination should be performed on animals of both sexes to ensure their optimal health at the time of breeding.

Canine estrous cycle and breeding management

Usually, pets owners have issues regarding heat detection and mating at the correct time. Optimum age of breeding at the correct time of the estrous cycle ensures fruitful pregnancy. The bitches are usually defined as non-seasonal monoestrous, polytochus and spontaneous ovulator.

The average age of puberty in bitches is 9 to 10 months, ranges from 6 to 24 months. The inter estrous interval ranges from 4 to 12 months with an average of 7 months. Normally, 3 estrous cycles occur in two years. There are four stages of estrous cycle i.e Proestrus, Estrus, Diestrus, and Anestrus. Both proestrus and estrus are called heat or season.

  • Proestrus

It is characterized by playful behavior and ends when female allows male for copulation. In this stage, attractiveness and receptivity for male gradually increase but the female does not allow the male to mount.

Follicles produce estrogen (Estradiol 17-β) which causes vulvar swelling, vaginal edema, cornification of vaginal epithelial cells, uterine bleeding and serosanguinous vulvar discharge. The thickness of stratified squamous epithelium of vagina increases.

Its average duration is 9 days, ranges from 3 to 17 days.

  • Estrus

It starts when female allows male for mating. The feet of the female firmly placed on the ground to allow the male to mount i.e. standing heat. The tail is somewhat side deviated to allow intromission i.e flagging. Swollen vulva becomes less turgid or flaccid.

In some cases, the vulvar discharge becomes less bloody but remains sanguineous in both phases in normal bitches. Mature oocytes have fertility life of 2 to 4 days and this period is called a fertile period. The capability of sperm for fertilization is 3 to 4 days as long as 6 days. The average duration of estrus is 9 days, ranges from 3 to 21 days.

  • Diestrus

No external signs can be visualized to discriminate it other than cessation of estrus signs. It is generally characterized by female behavior which becomes refractory to mating and diminishing attraction to a male. Edema becomes reduce and vulvar discharge diminishes. Vaginal mucosal folds become flattened and flaccid. Parabasal epithelial cells and neutrophils reappeared in vaginal cytology. Its average duration is 60 to 80 days.

  • Anestrus

It is marked by ovarian inactivity, endometrial repair and uterine involution which follows diestrus and ends with the onset of proestrus. It is generally termed as sexual quiescence. Its average duration is 4.5 months. Vaginal cytology reveals that mucosal folds become thin, flat and red. Endometrial sloughing occurs due to which the size and activity of endometrial glands, the thickness of myometrium and endometrium become decrease.

When to Breed Your Female Dog?

In order to breed your female dog with a male, you will have to determine that either your dog is at an optimal stage of the heat cycle or not. You can check it by her behavioral status/signs or by running tests. Once you are able to know the optimal stage of breeding, you can breed your dog properly.

  • Behavioral Signs

Check for Spotting:

You should notice your female dog is spotting around your home. The discharge will appear deep red or milky pink. It will have a strong and distinct smell to attract males. The female dog will become fertile after 12 days of this bloody discharge.

More Urination:

You should also pay attention to your dog how she often urinates. If she urinates in small quantity but more frequently, then she is likely in heat. She wants to get outside more to urinate. Her urine contains pheromones which attract males and let them know that she is interested in copulation.

Examine Genital Area:

When a female dog is going to heat, her vulva begins to swell, enlarged and protruding outward. The tip of vulva moves upward to make it easier for intromission.

  • Heat Cycle Tracking:

You may need to track your dog’s heat cycle to confirm the optimal stage for breeding.

Lab Tests:

  • Vaginal Smear Examination:

You can confirm the heat by performing a vaginal smear examination by your vet. He will take a vaginal swab from your dog to perform this test. It is a non-invasive technique and will not harm your dog. Your vet will examine the changes in vaginal cells of your dog under a microscope to confirm the time of ovulation.

  • Serum Progesterone Test:

You can also check your dog’s ovulation by having your vet to do a blood test to determine the level of progesterone. This test will require a blood sample from your dog. The doctor may need several blood samples to confirm. This test is considered accurate.

Breeding of Your Female Dog:

  • Premating Consultation:

The premating consultation is depended upon the owner’s knowledge and history of the patient. Clinical examination of both participants should be carried out to ensure the health status and breeding soundness. They should be sexually and skeletally mature as breeding in immature can cause dystocia (difficult birth).

Following points should be considered before breeding:

  • The animal’s medical and reproductive history
  • The animal’s body weight – problems of obesity and malnutrition
  • Pelvic capacity – it should be large enough to allow the passage of the fetus
  • Vaccination history – booster should be given before breeding
  • Examination of the genital area
  • Bacterial investigation of the genital tract
  • Monitor the approach of ovulation with the aid of progesterone profile and vaginal smear examination

Find a Suitable Male for Breeding:

You will need a suitable male for mating your female dog. Look for a dog of the same breed which is healthy and has no genetic faults. You should also confirm the age of the dog. Make sure to discuss with your vet before mating of your dog. Your vet will clear the dog health status to avoid breeding problems before the process.

Place of Mating:

Male dogs do better breeding when they mate on their territory or home. Before estrus, when the male and female partner have lived together for some time, they may be reluctant to breed. So, to eliminate this problem, it is wise to separate the pair before estrus is expected. The animal can be reintroduced for breeding once estrus has started.

Stress Free Environment:

You should bring your female dog to male in a stress-free environment. The breeding area should be clean and open. If your female dog is in optimal stage, she will warm up the male dog quickly.

Age of Breeding:

Male dogs become capable of breeding around the age of 6 months. If the dogs are used as professional stud later in life, they should not be breed for 1- 2 years.

The mature stud should have one bitch per week ideally. It is also evidenced that the breeding in bitches should not be delayed later than 3 years because the fertility gradually decreases as the age increases.

Bitches can be breed from the age of puberty until she gets ideal body weight and size i.e. 18 months. It is advisable not to present a bitch to male until he reaches the weight of 2.5 kg and one year old.

Time of Mating:

The correct timing of mating is the willingness of bitches to allow mating. Other indicators of potential receptivity include:

  • Cessation of proestral bleeding
  • Vulvar relaxation
  • Response to perineal stimulation
  • Vaginal cytology – showing cornified vaginal mucosal epithelium
  • Electrical resistance to the vaginal mucosa

Frequency of Mating:

Naturally, the male and female partners mate up to five times daily. In control breeding, mating should normally be allowed every 48 hours as long as the bitch remains receptive. Conception rate increases with increase in the frequency of mating.

Mating Behavior:

When the bitch is fully in estrus, she will allow mating after a period of play and mutual interest. During this period, the male dog sniffs the genitalia and attempts to mount.

The bitch raises a tail and shows no objection to being mounted. Canine tie phenomenon can prolong the coitus in dogs for up to one hour. Sedation of both partners with acepromazine or traditional method of applying cold water is effective to commence the postcoital tie. Optimal breeding management techniques can often result in the maximum reproductive efficiency desired.

Authors: Ali Murtaza, Adil Ali Abid, M. Sagheer, Dr. Ilyas Naveed and Wafa Yousaf, College of Veterinary and Animal Sciences, Jhang.