AI in the Bitch
When a bitch begins her heat cycle (Pro-estrus) her vulva will swell and she will bleed for three to nine days. During this time the uterus is growing a new lining for the embryo. When her bleeding subsides, she will be receptive to the stud and stand to breed (estrus). Standing heat can last three to seven days. This is the only part of her heat stage during which she can become pregnant. After the seventh day of estrus, she will enter "metestrus," and will repel a stud's sexual advances. Ovulation generally occurs at the end of or just after standing heat. The bitch is most fertile from four days before and three days after ovulation. That is the window we are trying to hit with our AI breeding. This is why we recommend to AI the female every other day to try to time it with her estrus.
Male Dog Arousal
The male dog must be excited in order to collect semen. Stud dog arousal is easily achieved when a female dog in estrus is placed near, or with the male. If no female dog is available that is currently in heat, breeders often keep a special supply of cotton swabs on hand. These cotton swabs were wiped across an estrus bitches vaginal area and stored in a refrigerator. The swabs can then be wiped across the vaginal area and back of a female and the male will think the female is in season when he “catches the smell” of estrus female.
Once excited, the male will attempt to mount the female dog. Before the male can insert his penis into her vagina, grasp the penis and place it into a semen collection receptacle. Keep massaging the penis to simulate the constriction of the vagina during normal breeding through the prepuce (sheath) until ejaculation occurs. Once the male dog adjusts to being assisted, the semen will easily be collected.
Once collected, withdraw the male's penis from the artificial vagina and draw up the semen in a syringe. Take the male out of the room to avoid having him try to mount the female again. Avoid temperature swings and cold shock of the semen until it is placed into the female.
Dogs weighing 10 pounds or less can collect 1.5 to 3 milliliters of semen. A dog weighing up to 50 pounds can collect 3 to 5 ml of semen and in dogs over 50 pounds, 5 to 8 ml of sperm per collection is possible.
Insemination should take place immediately after semen is collected from the male. The goal is to deposit semen directly in front of the cervix or as close to the cervix as possible. The length of the pipette depends on the size of the dog. The female is stood with her back legs behind her pelvis much like a show stack. This “Saw Horse stance” flattens the vaginal vault making insertion of the pipette to the cervix easier. A dog’s vaginal vault is one of the longest per pound of any mammal. It is up, over and down to get to the cervix but moving the back feet behind the bitch allows for a flatter route. Attach the syringe on one end of the pipette and insert the opposite end into the standing dog's vaginal vault. The pipette should be guided into the top of the vagina to avoid urethral entrance. Be gentle and travel up, then flat, then slightly down. Once pipette is in place you will deposit the semen. Then fill the syringe with air and push any remaining semen through the pipette into the vagina.
Keep the dog in a standing position for at least 10 minutes. Do not allow her to sit or urinate. After 10 minutes the dog can walk around normally, but best if you confine her to avoid jumping or urinating for at least an hour. After that hour of confinement, the dog can return to normal activity.
Storing and Freezing Semen
Semen is best inseminated immediately but if you must store, promptly refrigerate to ensure viability. It can safely be chilled for 24 hours with little damage to the sperm's viability. If semen is not going to be used within 24 hours of the semen collection, then the semen must be frozen for future use. Semen is processed, mixed with an extender that preserves it and slowly frozen in liquid nitrogen. Specialized veterinarians are trained and equipped to handle this for you. This freezing allows storage of genetics and insurance of fertility with a superior stud’s genetics. Adequate freezing guarantees the sperm's viability for future use.
The best success rate is achieved with fresh semen. When the female dog is promptly inseminated, the success rate varies with the skill of the breeder but mirrors natural breeding. When using semen that is fresh and has been chilled the success rate drops to 59 to 80 percent and frozen semen placed in the vagina beside the cervix holds a low success rate of only 52 to 60 percent.
Trans-Cervical insemination is a good technique to replace surgical insemination into the uterus. The frozen semen is visually placed into the actual uterus of the dog using a vaginal scope and guiding the catheter through the cervix. Trans-cervical insemination with frozen semen has a success rate of up to 80 percent.
- Dr. B
The materials, information and answers provided through this website are not intended to replace the medical advice or services of a qualified veterinarian or other pet health care professional. Consult your own veterinarian for answers to specific medical questions, including diagnosis, treatment, therapy or medical attention.
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