The dog’s sexual behavior

The male dog reaches puberty somewhere between the age of seven to ten months, depending on his breed. Small breeds are more precocious than medium-sized dogs and even more so than large-sized breeds. The extremes on either end are six months and three years. With bitches, sexual maturity or puberty corresponds to the first heat, which occurs between six and twelve months. The bitch has two estrous cycles per year. The onset of estrous does not seem to depend on the season, but there is greater frequency in autumn and spring.

How old is a male boxer puppy when he will reach sexual maturity?
Male dogs reach sexual maturity around 6-8 months of age.
How old is a female boxer puppy when he will reach sexual maturity?
Female dogs reach sexual maturity around 6-18 months of age. Most have their first heat at about 10 months.

The dog will be “in heat” for approximately three weeks. Pro-estrous corresponds to the first half of the heat. During this period, the bitch is not receptive to mounting, even though she is attracting males. Owners may observe a swelling of the vulva and loss of blood. Estrous occurs during the second half. The bitch becomes agitated and agrees to be mounted. She is most likely to allow the male to mount her from the 10th to the 12th day. Ovulation occurs around the 11th or 12th day. It occurs spontaneously and is triggered by the release of the luteinizing hormone or LH.
Some dogs, however, can still be impregnated two or more weeks after heat. The male’s spermatozoids are highly resilient and fertilization can be achieved in a female mounted at the end of pro-estrous. Bitches always ovulate several times. If several births occur, the puppies could be from different fathers. Bitches are in heat for an especially long period of time – two to three weeks on average. Once her heat is over, the cycle continues with a phase called metoestrus. Metoestrus lasts approximately four months. Sometimes a pseudo-gestation is observed, accompanied by a change in mood, the production of milk, etc. Anoestrus follows, which is a period of rest. It lasts one to two months. The average cycle length is six months (though it can last up to ten to twelve months without necessarily indicating the presence of a disease). Thus, the bitch is in heat twice a year.
The male detects a female in season by the scent of her urine, which contains metabolites of estrogens. During the estrous cycle, the female actively seeks out the male. When the two meet up, they explore each other through smell. Often, invitations to play are observed. If the female is in her pro-estrous cycle, she will not stand still long enough. She moves, turns around, lies down, stands back up, sits and the male is unable to mount her. During estrous, however, she will stand still long enough for the male to mount her.
It is easier for the male to mount the bitch in a familiar environment that is permeated with his scent. This is why the female usually comes to the male. A subordinate male or female may not mate in front of a dominant member. The dominant owner should never watch his male or female dog mate.
It is possible to prevent the female from going into heat through the use of hormonal contraceptives that temporarily suppress the cycle. The contraceptive can be administered either orally or through an injection. In either case, these products must be administered during a period of sexual quiescence, or anoestrus, which means two months before the estimated onset of the heat to be suppressed.
Contraception does have side effects. Among others, it may increase the risk of uterine infections. If the bitch is not intended for breeding, it is better to choose a more definitive solution, i.e. surgical sterilization through spaying. During this procedure, the bitch’s ovaries are removed, which means she will no longer have a sexual cycle. It is advisable to spay before the onset of puberty in order to reduce the risks of genital and mammary diseases.

Sexual Maturity
The dog’s sexual behavior. Sexual Behavior in Dogs. Sexual Behaviour in Dogs. Sexual maturity of a male? When is a female and male boxer ready to breed. Boxer Dog Puberty. Is my dog going through puberty? Canine sexual anatomy and development. At what age does a puppy mature?