The heat, what is it exactly?
Estrus in bitches corresponds to the periods of pro-estrus and estrus within the bitch's sexual cycle.
Proestrus marks the beginning of heat. This phase lasts from 5 to 20 days depending on the female dog. During this period, the ovarian follicles enlarge and secrete estradiol (estrogen), a hormone that causes the uterus to grow and the vagina and vulva to expand.
Estrus is the second phase of the heat period. It lasts from 3 to 10 days and includes ovulation.The ovaries then release primary oocytes which are not directly fertilizable by the sperm of a male dog. These oocytes still need to mature for 48 to 96 hours to become secondary oocytes that can be fertilized for a minimum of 48 hours. In other words, this means that a female dog has the highest chance of having puppies if she bred two to three days after ovulation.
When does the first heat appear in the female dog?
The female dog's sexual cycle and the onset of her first heat occurs around her 10 to 12 months on average. In small breed bitches and in the German Shepherd, they are generally earlier and can appear as early as 5 to 6 months of the animal. Conversely, in bitches of giant breeds, the first heat may not appear until around 24 months of the animal.
The first heat can be very discreet so that it can sometimes go completely unnoticed by the owner.
How often does the heat return and how long does it last?
The heat lasts on average 3 weeks, with possible individual variations and these heats return twice a year, with intervals of 6 months between each heat on average.
However, the interval between two periods of heat - called interoestrus - can be longer or shorter depending on:
- the breed of the dog. Some dog breeds are known to have “close” heats compared to the average of other female dogs. This is the case for some females who belong to the Rottweiler or German Shepherd breeds for which it is normal to express heat every 4.5 to 5 months. Conversely, other breeds of dogs have heats that are normally more spaced out: every 8 to 9 months for certain female Labradors or Collies, or even every 12 months for females belonging to so-called primitive dog breeds (closer to the wolf).
- the climate and/or the season. Unlike the wolf, which reproduces seasonally, the dog is able to reproduce all year round. However, the climate can influence the occurrence of heat and it would seem that in temperate climates, the majority of female dogs have their heat at the very beginning of spring.
- taking certain medications. Some medications can disrupt the rhythm of heat or even stop it completely. This is particularly the case for drugs containing steroids and antifungal drugs.
- or even the presence of other female dogs around her. When several female dogs live together, two phenomena can occur: their heats can synchronize or some female dogs can stop having heats. In the latter case, the fact of taking the female dog out of the pack is sometimes enough to make her heat express again.
Remember, however, that it is above all the regularity of the anestrus phase (" sexual rest" ) between two periods of heat that is important in a bitch more than the rate at which your bitch is supposed to have her heat .If a female dog who had regular heat begins to have heat that is further and further away or, on the contrary, closer together, it is advisable to consult a veterinarian without waiting too long. This change of rhythm can indeed reflect an ovarian problem or dysendocrine.
Is there menopause in bitches?
No. Dogs do not know the period of menopause like humans do, during which menstruation and ovulation stop. Bitches therefore ovulate all their life, even if heat can become less frequent or much more discreet in older bitches.
How do I know if my dog is in heat?
The heat period is accompanied by physical signs and a change in your dog's behavior.
During heat, you may notice a change in behavior in your female dog. The latter can become very cuddly or even a bit sticky or, on the contrary, become more aggressive.Other female dogs are generally poorly accepted while the company of males is rather sought after during estrus, even if it means running away from your home to find one!
Apart from behavioral changes, physical and physiological signs will tell you if your dog is in heat.
During the first phase of heat called pro-oestrus, the bitch's vulva increases in volume and vulvar blood loss appears. These blood losses are more or less important according to the female dogs. The female emits sex pheromones in her urine and vaginal secretions which are perceived by the males and attract them. However, the female dog still refuses mating during this phase.
During the second period of heat during which ovulation takes place - called estrus - the vulva becomes even more swollen and the vulvar discharge decreases and clears up to sometimes stop completely.The female dog also places her tail to the side when a dog sniffs her hindquarters. It is during this period that the female accepts the mating and is likely to be fertilized by a male. Acceptance of the male lasts longer or shorter depending on the females, from a few hours to more than a week for some of them.
" Can we calm a dog&39;s heat?"
The heat is a natural and temporary physiological phenomenon that you will have to take patiently if you do not want to have your dog sterilized. Be aware that there are also “birth control pills” for female dogs but their long-term use is not recommended because it causes side effects. In order to calm the undesirable behavior of a female dog in heat, it is possible to use homeopathy to “curb her heat”. You can thus safely try to administer a homeopathic sexual sedative, or a dose of Ovarinum or Folliculinum 30CH, but only if you do not wish to reproduce it.
To sum up, the essential points to remember:
- The first heat appears at puberty in the female dog: between 6 and 24 months, with an average age of onset at 10-12 months. They are generally discreet.
- A dog systematically ovulates during her heat. It is during this period that she is most likely to agree to be ridden by a male and that she can be impregnated.
- The heat period lasts about 3 weeks on average in bitches.
- A female dog usually has her heat twice a year but more than the frequency of the heat, it is their regularity that matters the most.
- The heat period is accompanied by hormonal variations, physical signs and a change in behavior of your bitch (and surrounding dogs) summarized in the table below:
| Average duration | Hormonal variations | Visible physical signs | Behavioral Changes | ||
|
Heat season (3 weeks on average) | Proestrus | 5 to 20 days | Rising estrogen Almost zero progesterone | Very swollen and turgid vulva
Vulvar blood loss | Male attraction
Mating refusal |
| 3 to 10 days | LH peak on 1st day of estrus
Decreased estrogen and increased progesterone | Less swollen vulva
Vulvar discharge lighter to absent | Attraction of males and acceptance of mating | ||
| Metoestrus or diestrus | 57 to 65 days | High progesterone (hormonal impregnation) and fall at the end of the phase | Pregnancy or not
At the end of this period: putting or possibly lactation of pseudogestation | Refusal of the male | |
| Anestrus | 2 to 9 months | Oestrogens and Progesterones secreted in small quantities | No discharge and vulva of normal size (reproductive system at rest) | Nil | |
Atypical heat in bitches
In some female dogs, it happens that heat does not follow the usual pattern described above. We then speak of atypical heat.
Among these atypical heats, we can observe:
" Silent" heat
We speak of "silent" heat in bitches when the clinical signs of heat are very discreet or even non-existent: little or no vulvar discharge, absence of swelling of the vulva and no attraction of males.
These silent heats usually occur during the female dog's first heat or in bitches over 10 years old. Some small breed female dogs can also present this type of atypical heat.
Just because the dog's heat goes unnoticed or almost unnoticed doesn't mean the dog doesn't ovulate.
False heat
False heats are also known as split-heats, disjoint heats or even fractionated heats.
At first, bitches normally go into heat: they show vulvar blood loss for 3 to 10 days, attract males and sometimes even accept mating.Then, the heat stops abruptly without ovulation occurring. After a few days or weeks, normal heat (accompanied by ovulation) resumes. Most often, it is young female dogs under 2 years old who experience this phenomenon of false heat which, moreover, has no impact on their fertility.
Persistent heat
Persistent heat is very long or even continuous heat in the female dog. They often reflect the presence of an ovarian cyst or a problem of hyperestrogenism and are most often found in older bitches. The occurrence of this persistent heat justifies a consultation with the veterinarian.
Synchronized heats
Synchronized heats appear at the same time as the heats of other female dogs when the latter live in a community. Conversely, heat can be inhibited if the female dogs, usually living in a community, are taken out of the group.
Dealing with bitch heat
If you don't want your dog to make a litter then it will be necessary to take some precautions throughout her heat:
- During walks, keep your dog on a leash. Even if your bitch usually shows excellent recall, her heat could well cause her to exceptionally disobey you to meet a nearby male, especially during her fertile period,
- If you have a garden, make sure to secure it so that your dog does not run away during her heat and that the male dogs in the area cannot physically come and visit her. Failing this, there are many risks: road accident, fine, impoundment, neighborhood problems in the event of a runaway or unwanted litter in the event of an impromptu visit from a male dog.
You will also need to resort to the use of sanitary protection for your dog so that she does not dirty your interior when she loses blood. There are protective panties for dogs in which you can add sanitary napkins or disposable dog diapers. Although blood loss is usually minimal, it can still stain textiles very strongly. It is best to accustom your bitch gradually and positively to wearing these protections and well before the heat so that she accepts them more easily the day she needs them.
Can we "stop" the dog's heat?
Only means of contraception prevent the occurrence of ovulation and those of heat. This contraception can be temporary (in the case of “contraceptive pills”) or irreversible (in the case of surgical sterilization).If you do not want your bitch to reproduce, it is the second solution which is to be preferred because it cancels the risk of developing a pyometra, a serious infection of the uterus and, when it is carried out before the first heats, it is known to reduce the risk of breast tumor occurrence.
How to know the time of ovulation in a female dog in heat?
If you want your dog to have babies, it can be interesting to precisely determine the moment of her ovulation, in other words the ideal moment for mating in order to maximize the chances of procreation. This is all the more useful if the owners of the breeding male need to travel several hundred kilometers to mate or if the female dog has already been bred several times without results.
To do this, the veterinarian can perform vaginal smears and a hormonal progesterone assay.In practice, all you have to do is take your dog to the vet 5 to 6 days after the start of her heat to start monitoring by taking a vaginal smear. Depending on the observation of the cells present on the smear, the veterinarian will be able to determine if the female dog is more at the beginning of pro-estrus or at the end of pro-estrus. If the female dog is at the beginning of pro-oestrus, it is because her ovulation is not for now! On the other hand, if it is at the end of the phase, the veterinarian will take a blood test to measure the progesterone. It is this dosage that will confirm or not ovulation.
Medically monitoring your dog's heat can therefore require 3 to 4 visits to the veterinarian, but it is the most precise way to determine the moment of ovulation.
Of course, it is also possible - in a more empirical way - to rely on observation of the female dog and her behavior.Thus, the decrease in vulvar discharge and their clarification are signs that slightly precede ovulation. The acceptance of the male is an unreliable criterion because it can occur up to two days before ovulation. It is also not systematic in all bitches in heat because bitches do not always accept the males that have been chosen for them. Some female dogs with a strong temperament or particularly fearful may refuse the mating when they are in the estrus phase.