1. Female dog's reproductive organs: The structure and location of the female dog's reproductive organs:

Ovaries: located in the lower part of the waist, Below the 4th to 5th lumbar vertebrae, there are two oval ovaries, located at the two ends of the left and right uterine horns, connected to the uterus by ovarian ligaments, and in contact with the funnel-shaped umbrella of the fallopian tube. Its function is to produce eggs and secrete hormones. The structure of the ovary is composed of a cortex surrounded by a membrane.

Fallopian tube: The tube that connects the ovary and the uterus. After the follicle matures in the ovary, it moves along the fallopian tube and enters the uterine horn.

The uterus: is where the fetus develops. The uterus is an empty muscular organ in the middle, which is connected to the fallopian tubes forward, and leads back to the vagina, with the bladder below and the rectum above. Most of the uterus is in the abdominal cavity, and a small part is in the pelvis. The whole uterus is divided into one body, one neck and two horns. The dog's uterus is very short, and the uterine horns are very long. From the appearance, the uterus looks like the English letter Y.

Vagina: The passage that communicates with the uterus to discharge the fetus and urine. The upper part has the rectum, and the lower part is in contact with the bladder and urethra. The structure of the vagina has two layers, one is the longitudinal muscle fiber layer, and the other is the annular muscle fiber layer.

Pussy: Located between the anus and the pubic bone, it is shaped as a vertical slit with labia on either side. The upper commissure is acutely angled, and the lower commissure of the two lips is round and thick. Its structure has a very thin outer skin, smooth and colored, with many sebaceous glands and sweat glands, and a layer of striated muscle under the skin, which contracts the vulva.

2. Male dog's reproductive organs:

Testis and epididymis: There is a pair of testis, located in the scrotum, oval in shape, slightly on both sides Flat and composed mainly of curved seminiferous ducts, which are made up of the glandular tissue of the testes and whose function is to produce sperm.

The epididymis is closely connected with the testis, it is a curved tube, the head is connected with the efferent duct of the testis, and the tail is connected with the vas deferens, its function is to make the sperm discharged from the testicular fine duct to stay here for a period of time. , and make the development of sperm more fully, more perfect, while the secretion of epididymis helps sperm activity.

Vas deferens: shaped like a duct, it is composed of well-developed smooth muscle, so it has the effect of ejaculation. One end is connected to the tail of the epididymis, the other end is located in the upper part of the bladder, and migrates to the pelvic urethra through the seminal vesicles, and is discharged from the urethra during ejaculation.

Prostate (Prostate): Located in the continuum of the bladder neck and urethra, it is also composed of glands with secretory function to enhance sperm motility. Penis: The penis is a mating organ, which is divided into three parts: the root of the penis, the body of the penis and the head of the penis. The penis is made up of spongy tissue. The spongy tissue expands when the veins are congested and is elastic, so the penis can increase or elongate in volume. When the penis is in this state, it is called an erection. At the end of the penis is a longer glans, with small pieces of bone in it.