The continuous estrus of a female dog means that the estrus time of the female dog is prolonged and greatly exceeds the normal estrus period. This is mainly due to the ovarian cyst of the female dog or the inability of the follicles on both sides of the female dog to develop at the same time. It is very obvious when using animal B-ultrasound examination.

Ovarian cysts in female dogs are mainly follicular cysts. At this time, the ovaries of the estrus female dog have mature follicles, which are getting bigger and bigger, but they just don't rupture, while the follicle wall continues to secrete estrogen. Follicular cysts are very obvious in animal B-ultrasound observation. Under the action of estrogen, the estrus time of the female dog will be prolonged. At this time, if the corpus luteum secretion in the estrus female dog is less, the estrus performance of the female dog is very strong; on the contrary, if the corpus luteum secretion in the body is too much, the estrus performance of the female dog is depressed.

The follicles on both sides do not develop at the same time. The main manifestation of animal B-ultrasound observation is that when the female dog is in estrus, one ovary has follicles, but the development stops after a few days, while the animal B-ultrasound can be observed that the other ovary has follicles, which prolongs the time of estrogen secretion in the female dog and prolongs the estrus time of the female animal.

Failure to estrus on time, the estrus cycle of breeding female dogs is generally from 4 to 6 months, and estrus will occur at that time, but there are also a few female dogs that have never shown estrus symptoms. This situation is mostly caused by malnutrition, old age, lack of exercise, mesometritis, and persistent corpus luteum in the ovaries. Therefore, animal B-ultrasound is needed to identify these diseases and then carry out targeted treatment.

When a breeding female dog shows abnormal estrus, we must first distinguish the situations and treat them differently. That is, those who are too old or suffer from chronic reproductive tract diseases and have no breeding value should be eliminated. Animal B-ultrasound examination shows that female dogs who are too thin and have poor nutritional status should be provided with sufficient nutrients by adjusting their daily diet, especially to meet their needs for protein, energy and vitamins, so as to promote their overall development and enter normal estrus. We can also calculate and grasp the next possible estrus time based on the last birthing time, and pay attention to observation, breed at the right time, or use animal B-ultrasound for identification. Young female dogs should not be bred too early, and they must wait until they are mature before estrus breeding can be carried out.