In general, puberty occurs between 6 months for small breeds, and 18 months for giant breeds.This is the first production of sperm.
Then follows the best time for breeding.
Then, fertility gradually decreases with age, and that at 7 years for giant breeds, a little later in medium and small breeds.
THE DOG:
Puberty appears, as for males, between 6 months and 18 months after the race. It is the ability to ovulate and manifested by the first heat. These are usually very discrete, and teachers do not recognize it. Being puberty for the female does not mean that it is able to complete gestation and parturition. It is better to let the first heat of the dog before considering a coupling, to be sure the full development of the pelvis and reproductive tract.
There is generally no menopause, however, in older dogs (over 10 years), the heat may space themselves.
REPRODUCTIVE FUNCTION IN THE DOG:
Sexual function is mainly conditioned by the perception of pheromones (odorants) emitted by the dogs during hot weather. During this period the male may lose appetite, run away or rubbed on the legs of his master or mistress, or even aggressive.
During this period, it is possible to counteract the sexual activity by hormone treatment or tranquilizers. But, beware of side effects! Your vet will advise.
Contraception:
For a final neutralization of sexual activity among males, should be considered a surgical castration (removal of testicles). This makes the dog sterile, and if castration is done before age 1 or 2 years (after the race), the behavioral manifestations disappear.
Outside of castration, one can perform a vasectomy (ligation of the vas deferens) that makes the dog infertile but free to express their sexuality (behavioral manifestations).
The traits of each animal are not changed by castration, for cons, there is often a decrease in aggression in some males.
REPRODUCTIVE FUNCTION IN THE DOG:
The sexual cycle:
From puberty, the cycle in the bitch, is on pace biannual (spring and fall). There is only one cycle per season, it manifests itself in the "heat".
The "heat":
Their duration is about 3 weeks with:
First time called "pro-estrus, a period of 7 to 11 days but sometimes up to 20 days. During this period, the vulva is swollen with bloody discharge. While attracting males, the dog refuses mating away, sitting, or even expressing a certain aggressiveness.
A second time called "estrus", a term average of 8 to 10 days but can vary between 3 and 20 days. Losses vulvar become clearer, less bloody. The vulva becomes less edematous and relieves congestion. This is the time of ovulation which occurs usually around the 2nd or 3rd day of estrus, the bitch is so fertile for a period of 12 to 72 hours.
This period is when the bitch attracts males and agrees to mate with the appearance of postural reflex (the female, still raises its tail, to set it on the side).