Dog Breed Mating
As A general rule, a bitch comes in heat every six months after her first period, but there are many exceptions. I have one bitch whose seasons come every seven months, while others vary, with sometimes five months and sometimes as much as seven or eight months separating them. The duration of these periods varies also, though the normal time is from two to three and o
ne-half weeks. However, it sometimes happens that a bitch will remain in heat for such a short period as one day, while others are all over it in several days. This is not hereditary. I had one bitch which I kept for two years without having once been able to detect a sign of her having been in heat, though her dam is as regular as clockwork. Neither does diet have any effect.
This variation may be due in part to evolution. The changed conditions under which dogs are living today as compared with former times will naturally have an effect on their organic systems, and it is quite probable that one indication of this evolution may be displayed by the varying heats. But nature never runs to schedule, and heats vary in all animals just as warm weather never comes on the same day two years in succession. Certain breeds are more likely than others to be irregular, just as certain breeds are harder to mate.
A bitch usually comes in heat for the first time around the age of eight or nine months; smaller breeds are earlier. That she will also come in about four months after she has whelped a litter is another point to keep in mind. If a bitch is early with one period, she will probably be late with her next. If she comes in at five months, she will probably take seven the next time, so that by the end of a little over a year she will have had two heats. Thus nature straightens out these irregularities over a period of time.
Sometimes what is known as a false heat takes place. The causes are not altogether known, but the symptoms are practically the same. The external organs swell and there is a discharge. Sometimes the bitch will accept the stud, but no pregnancy can follow. This occurred in my own kennels recently. A bitch came in heat, as I thought, at her regular time; she accepted the dog and the mating was carried out. But about a month later she again came in heat and the whole operation had to be repeated.