Artificial insemination technology is an important method for pig farms to improve breeds and increase production efficiency. Its advantages are mainly reflected in four aspects: First, it improves the utilization rate of excellent boars, which is conducive to breed improvement; second, it reduces the contact between breeding pigs, which is conducive to reducing the risk of disease transmission; third, it overcomes the physical differences between boars and sows, which helps to exert hybrid advantages; fourth, it is conducive to saving manpower and financial resources and improving economic benefits.
Semen examination
Before each insemination, the semen should be examined under a microscope. The qualified ones will be used and the unqualified ones will be discarded. The semen taken out from the 17℃ semen storage box should be preheated to 37℃ to check the semen vitality. The semen vitality ≥0.7 is qualified.
Semen temperature and dosage
Now semen is mostly stored in a constant temperature box, and the controlled temperature is 17℃. If the semen suddenly rises from low temperature to high temperature, the sperm is prone to stress death. Therefore, before insemination, the semen should be gradually raised to room temperature, and then insemination.
Generally, the insemination dose is not less than 20ml, and the effective sperm density is not less than 30 million/ml. In this case, the insemination effect will be better. The insemination volume of lean sows is significantly different from that of local pigs. The insemination volume of lean multiparous sows needs to be 100ml, and that of reserve sows needs to be 80ml; the insemination volume of local pigs can be 40ml.
Points to note for insemination operation
Secure the sow, and clean the sow's vulva, tail root and buttocks with a 45℃ 0.1% potassium permanganate aqueous solution, then soak a towel with warm water and dry the vulva.
Apply lubricant to the front end of the vas deferens sponge head: Take out a disposable vas deferens that is not contaminated from the sealed bag (hands should not touch the front 2/3 of the vas deferens), and apply erythromycin ointment on the front end as a lubricant.
Insert the vas deferens into the sow’s reproductive tract: Use both hands to separate the sow’s vulva, then use your left hand to keep the vulva open, insert the vas deferens upward at a 45-degree angle into the sow’s reproductive tract for about 10 cm, and push the vas deferens flat. When you feel resistance, continue to slowly rotate to the left and force the vas deferens forward until you feel the front end of the vas deferens is locked (it cannot be pulled back gently).
Insemination: Take out qualified semen from the semen storage box, confirm the boar breed and ear number; slowly shake the semen upside down, open the seal of the semen bag to expose the plastic tube, connect it to the vas deferens, lift the rear end of the semen bag, and start insemination (you can also put the semen bag on the vas deferens first and then insert the vas deferens into the sow’s reproductive tract); during the insemination process, you should constantly touch the sow’s breasts or vulva, press the back, and touch the sow’s ventral side to stimulate the sow, so that its uterus contracts to generate negative pressure and absorb the semen.
Prevent semen from flowing back. The speed of semen outflow can be adjusted by controlling the height of the semen bag. The insemination time is generally 3-7 minutes. After insemination, a small section of the rear end of the vas deferens can be folded up and fixed with the round hole on the semen bag, so that the insemination device can be retained in the reproductive tract for 3-5 minutes, and the vas deferens can be slowly slipped down; or after the semen is infused, the vas deferens can be pulled downward at a faster speed to stimulate the contraction of the cervical opening and prevent semen from flowing back.
The insemination time has a great influence on the litter size. According to the data, if the insemination time is less than 3 minutes, the average number of live piglets born per litter is 9.1, and if it is 3-4 minutes, the average number of live piglets born per litter can be increased to 10, and if it exceeds 5 minutes, the average number of live piglets born per litter can reach 11.37.
A new disposable vas deferens should be used for each sow for each insemination to prevent the occurrence of metritis.
For multiparous sows, a disposable sponge-head vas deferens should be used. Check whether the sponge head is loose before insemination; for reserve sows, a disposable spiral-head vas deferens should be used.
Dealing with abnormal problems during insemination
If the sow urinates when the vas deferens is inserted, the vas deferens should be discarded (multiple vas deferens should be taken back and disinfected again).
If semen flows back during insemination, the semen bag should be lowered to allow the semen in the reproductive tract to flow back into the semen bag, and then the semen bag should be slightly raised to allow the semen to slowly flow into the reproductive tract. At the same time, pay attention to compressing the sow's back or massaging the sow's flank and breasts to promote uterine contraction. If the problem still cannot be solved, the vas deferens can be moved forward and backward, or the vas deferens can be pulled out, reinserted and locked, and then insemination can be continued.
Number of inseminations. Generally, multiparous sows are inseminated twice in one mating estrus period, and reserve sows are inseminated three times in one mating estrus period. 18 hours after the last insemination, the sow should be checked to see if it has passed the estrus period. If it has not passed the estrus period and there is still a standing reaction, it should be inseminated again. The interval between two inseminations is generally 8-12 hours.
Carefully register the sow production card and breeding records.
Semen examination
Before each insemination, the semen should be examined under a microscope. The qualified ones will be used and the unqualified ones will be discarded. The semen taken out from the 17℃ semen storage box should be preheated to 37℃ to check the semen vitality. The semen vitality ≥0.7 is qualified.
Semen temperature and dosage
Now semen is mostly stored in a constant temperature box, and the controlled temperature is 17℃. If the semen suddenly rises from low temperature to high temperature, the sperm is prone to stress death. Therefore, before insemination, the semen should be gradually raised to room temperature, and then insemination.
Generally, the insemination dose is not less than 20ml, and the effective sperm density is not less than 30 million/ml. In this case, the insemination effect will be better. The insemination volume of lean sows is significantly different from that of local pigs. The insemination volume of lean multiparous sows needs to be 100ml, and that of reserve sows needs to be 80ml; the insemination volume of local pigs can be 40ml.
Points to note for insemination operation
Secure the sow, and clean the sow's vulva, tail root and buttocks with a 45℃ 0.1% potassium permanganate aqueous solution, then soak a towel with warm water and dry the vulva.
Apply lubricant to the front end of the vas deferens sponge head: Take out a disposable vas deferens that is not contaminated from the sealed bag (hands should not touch the front 2/3 of the vas deferens), and apply erythromycin ointment on the front end as a lubricant.
Insert the vas deferens into the sow’s reproductive tract: Use both hands to separate the sow’s vulva, then use your left hand to keep the vulva open, insert the vas deferens upward at a 45-degree angle into the sow’s reproductive tract for about 10 cm, and push the vas deferens flat. When you feel resistance, continue to slowly rotate to the left and force the vas deferens forward until you feel the front end of the vas deferens is locked (it cannot be pulled back gently).
Insemination: Take out qualified semen from the semen storage box, confirm the boar breed and ear number; slowly shake the semen upside down, open the seal of the semen bag to expose the plastic tube, connect it to the vas deferens, lift the rear end of the semen bag, and start insemination (you can also put the semen bag on the vas deferens first and then insert the vas deferens into the sow’s reproductive tract); during the insemination process, you should constantly touch the sow’s breasts or vulva, press the back, and touch the sow’s ventral side to stimulate the sow, so that its uterus contracts to generate negative pressure and absorb the semen.
Prevent semen from flowing back. The speed of semen outflow can be adjusted by controlling the height of the semen bag. The insemination time is generally 3-7 minutes. After insemination, a small section of the rear end of the vas deferens can be folded up and fixed with the round hole on the semen bag, so that the insemination device can be retained in the reproductive tract for 3-5 minutes, and the vas deferens can be slowly slipped down; or after the semen is infused, the vas deferens can be pulled downward at a faster speed to stimulate the contraction of the cervical opening and prevent semen from flowing back.
The insemination time has a great influence on the litter size. According to the data, if the insemination time is less than 3 minutes, the average number of live piglets born per litter is 9.1, and if it is 3-4 minutes, the average number of live piglets born per litter can be increased to 10, and if it exceeds 5 minutes, the average number of live piglets born per litter can reach 11.37.
A new disposable vas deferens should be used for each sow for each insemination to prevent the occurrence of metritis.
For multiparous sows, a disposable sponge-head vas deferens should be used. Check whether the sponge head is loose before insemination; for reserve sows, a disposable spiral-head vas deferens should be used.
Dealing with abnormal problems during insemination
If the sow urinates when the vas deferens is inserted, the vas deferens should be discarded (multiple vas deferens should be taken back and disinfected again).
If semen flows back during insemination, the semen bag should be lowered to allow the semen in the reproductive tract to flow back into the semen bag, and then the semen bag should be slightly raised to allow the semen to slowly flow into the reproductive tract. At the same time, pay attention to compressing the sow's back or massaging the sow's flank and breasts to promote uterine contraction. If the problem still cannot be solved, the vas deferens can be moved forward and backward, or the vas deferens can be pulled out, reinserted and locked, and then insemination can be continued.
Number of inseminations. Generally, multiparous sows are inseminated twice in one mating estrus period, and reserve sows are inseminated three times in one mating estrus period. 18 hours after the last insemination, the sow should be checked to see if it has passed the estrus period. If it has not passed the estrus period and there is still a standing reaction, it should be inseminated again. The interval between two inseminations is generally 8-12 hours.
Carefully register the sow production card and breeding records.