Sexual adolescence (puberty) occurs in females at approximately 8-12 months (with extreme values about 6-24 months). The onset of puberty is influenced by various factors, especially breeding predisposition, nutrition, breeding environment (number of dogs, calm / stress, etc.)

The first season may be a little different from adulthood. Sometimes so-called silent heat can occur in females, where the typical symptoms (swelling of the vulva, bleeding ...) owner may not even notice. The only sign of silent heat may be increased interest of dogs.

Sex cycle (heat) occurs in females mostly twice a year, less often once a year. The cycle itself consists of four phases, technically called Proestrus, Estrus (heat itself), Diestrus and Anestrus.

• Proestrus - the duration of this phase is usually 7-9 days. It is manifested by swelling of the vulva and bloody discharge from the genital organs. The female is attractive for dogs, but herself does not show any interest in mating, on the contrary she refuses and drives away.
• Estrus - the duration of this phase is usually 5-9 days. It is manifested by changes in the color and consistency of the vaginal discharge, which changes from blood red to pink or yellow. The bitch shows interest in the dogs, lets them jump on themselves and puts the tail to the side.
• Diestrus (also known as Metestrus) - is manifested by the gradual disappearance of the symptoms of heat, swelling of the genital organs disappears, the bitch is no longer interested in dogs.
• Anestrus - is a period of sexual peace. It can be quite difficult to delimit from the previous phase, Diestrus. This period ends with the onset of a new sexual cycle.