Quick facts
- Review the reproductive anatomy of the cow, heat detection, semen handling and the process to breed the cow to prevent common mistakes.
- First-time conception rate in virgin heifers should be 55% or more.
- For lactating cows, the goal should be a conception rate of 40% or more.
- Semen should be thawed at 95°F for 45 seconds.
- Use your left hand in the rectum and right hand to guide the insemination gun regardless of your dominant hand.
- Slowly deposit semen - it should take about 5 seconds.
- After breeding is complete, re-check that the desired bull was used for the mating.
Herd breeding goals
In virgin heifers, a reasonable goal is a first-time conception rate of 55% or more, or fewer than 1.8 services per conception.
For lactating cows, the goal should be a conception rate of 40% or more, or fewer than 2.5 services per conception.
Getting the cow ready
First and foremost, the cow must be ready to be bred. This can be determined by noting signs of estrus or based off a timed synchronization program.
Properly restrain the cow when it is time to breed; it is important for both the cow’s and inseminator’s safety. Pick a place that is easy to use and is familiar to the cow to reduce the stress of the situation.
Proper semen handling
Store insemination supplies and semen tanks in a clean and dry location at all times. Keep accurate records as to semen location within the semen tank and the number of units available.
|
- Using tweezers, quickly remove the desired straw of semen from the goblet below the frost line.
- Don’t use your finger as it potentially leads to thawing the semen too quickly.
- If you have multiple cows to breed, only thaw the number of straws of semen that can be successfully used within 15 minutes of thawing.
- Shake the straw after you remove it from the semen tank to eliminate any liquid nitrogen at the end of the cotton plug.
- This step prevents damage to the semen straw when it is placed in the water bath to warm.
- Semen should be thawed at 95°F for 45 seconds.
- Be sure to check your thermometer for accuracy. Improper thawing temperate can significantly affect the quality and viability of semen.
- While the semen is thawing, record the date, cow name and number, and bull ID in your record keeping system. After the straw is thawed, dry it off with a clean towel and verify that you have grabbed the correct semen straw for the desired mating.
- Warm the breeding gun by stroking vigorously with hand five or six times.
- Make sure that you pull the plunger back about six inches to prepare for the semen straw. Place the end with the cotton plug in the gun.
- Cut the sealed end at a 90° angle about one-fourth inch from the end. If not cut correctly, the plastic sheath may not seal tightly resulting in back flow of semen between the straw and sheath.
- Place the sterile sheath over the gun and push on until it seals. Sheath protectors can also be helpful to maintain a clean gun for insemination.
- Place the gun between your body and shirt to maintain optimal temperature until you are ready to breed the cow.
Breeding the cow
It is recommended to use your left hand in the rectum and right hand to guide the insemination gun regardless of your dominant hand. Use a new breeding glove for every insemination.
- Lubricate the glove with mineral oil or a commercial A.I. lubricant.
- Let the cow know that you are there by gently patting her on the rump or talking in a soft voice. Enter the rectum by forming a cone like shape with your fingers. Gently palpate the cow and remove any excess manure.
- Place the tail on the back side of your left arm so that it is not in the way during insemination.
|
- Wipe the vulva and the underside of your palpating arm clean of any manure with a paper towel. This will help prevent any contamination when inserting the loaded gun into the cow’s reproductive tract.
- With your left hand make a fist and press down directly on top of the vulva. This will spread the vulva lips allowing easy access to insert the gun.
- The insemination gun should be inserted into the vulva upwards at a 30° angle. This helps to prevent the gun from accidentally being inserted into the bladder.
- When the gun is 6 to 8 inches inside the vagina, raise the rear of the gun to level position and slide forward until it contacts the beginning of the cervix. If the gun is getting caught in the folds of the cervix, try stretching the cervix away from you with your left hand to free the gun and allow easier passage to the cervix.
- Place the cervix onto the insemination gun.
- Provide forward pressure on the gun while manipulating the cervix slightly ahead of the gun.
- Never force the gun through a tough part of the cervix.
- Progress is made with the hand inside the cow manipulating the cervix, not the one holding the gun.
- Be patient as you work through the rings of the cervix.
- Once you have cleared all the cervical rings, the gun should slide forward freely with little resistance.
Ideally, semen should be deposited just beyond the cervix into the uterine body. Depositing the semen in the uterine body allows the semen to evenly distribute between both horns.
- Slowly deposit semen - it should take about 5 seconds.
- Be sure that your fingers of the palpating hand are not blocking the flow of semen or a uterine horn.
- Be sure to maintain gun position so that the gun does not pull back into the cervix when depositing the semen.
- If the cow is moving and the insemination gun slips back through the cervix ring, correctly reposition the gun tip before continuing semen deposit.
- Gently remove the gun and check for any abnormal discharge. If abnormal discharge is present, note it in your breeding records.
- Before taking off breeding glove, remove the used sheath from the gun.
- Remove the glove starting at the top of the arm by turning it inside out as you remove it. Release the remaining air from the glove and tie it off; trapping the manure and used sheath inside.
- Re-check that the desired bull was used for the mating.
- Dispose of used glove in a proper location.
- Clean equipment and return to storage location.
Reviewed in 2023