Operation process of artificial insemination technology in pig industry

Operating procedures for pig artificial insemination technology

Artificial insemination of pigs refers to a breeding method in which male pig semen is collected using instruments, examined, processed, and stored, and then injected into the reproductive tract of estrus sows using instruments instead of natural mating.
The advantages of artificial insemination:
1. Beneficial for preventing infectious diseases.
2. Improve the utilization rate of boars.
3. Beneficial for the promotion of excellent varieties and superior paternal lineages.
4. It is possible to fertilize and mate estrus sows in a timely manner.
5. It can overcome the difficulties of excessive differences in body size between sows and those who are not suitable for local crossbreeding.
6. Can improve mating performance
7. Can reduce costs
1、 Training of Sperm Picking Boars
1. First, train the male pig with strong sexual desire, and then observe and learn from the next one in the fence.
2. Clean the abdomen and foreskin of the male pig, squeeze out the accumulated urine from the foreskin, and massage the foreskin of the male pig.
3. Inducing Crossing: Apply urine or vaginal secretions from estrus sows onto fake Taiwan pigs, while imitating the sow's cry. Alternatively, apply urine or saliva from other boars onto fake sows, all with the aim of inducing their desire to cross.
4. When none of the above methods are effective, you can come to an estrus sow and let the boar crawl several times empty. When the boar is very excited, drive away the estrus sow.
5. After the boar climbs onto the fake platform animal, it can start collecting semen.
6. Successfully trained boars should be harvested every other day within a week to consolidate their memory and form conditioned reflexes. For difficult to train boars, multiple brief training sessions can be conducted 4-5 times a week, with each session lasting up to 15-20 minutes. If a boar shows signs of boredom, frustration, or loss of interest, training should be stopped immediately. Reserve boars usually start collecting semen and training at the age of 8 months.
7. Attention: When the boar is very excited, pay attention to the safety of the boar and the sperm collector themselves, and the sperm collection pen must have a safety corner.
Regardless of the training method, the boar must undergo sperm collection after climbing over, otherwiseBoars can easily lose interest in crawling across sow beds. When training, it is not allowed to have two or more boars together at the same time, in order to avoid causing fighting among the boars, which may affect the progress of training and cause unnecessary economic losses.
II Collecting essence
1. Preparation of semen collection cup: First, place a disposable food bag inside the insulated cup, then cover the cup mouth with four layers of degreased gauze and fix it with rubber bands. Loosen it slightly so that it can sink to about 2cm. After preparation, place it in a 37 ° C constant temperature incubator for future use.
2. Before collecting semen, cut off the coat on the foreskin of the male pig to prevent interference with semen collection and bacterial contamination.
3. Drive the male pigs to the sperm collection pen, wash their abdomen and foreskin with 0.1% KMnO4 solution, then rinse with clean water and wipe dry.
4. Squeeze out accumulated urine from the foreskin, massage the foreskin of the male pig, and wait for the male pig to climb onto the fake Taiwan pig. Use warm and clean hands (with or without gloves) to grip the protruding glans, bend and straighten the 'S' shape of the penis when thrusting forward along with the male pig, grip the spiral and second folds of the penis tightly, and allow the penis to naturally stretch when thrusting forward without strong pulling. After full extension, the penis will stop advancing and reach a state of rigidity and "locking", starting to ejaculate. Do not let go during ejaculation, otherwise reducing pressure will cause ejaculation to be interrupted.
5. Collect concentrated semen until the boar has ejaculated, then let go. Be careful to prevent foreskin fluid from entering the semen collection cup during the semen collection process.
6. Be careful not to touch the penis during the semen collection process, otherwise the penis will quickly retract.
7. Clean the collection column before leaving work.
8. Sperm collection frequency: twice a week for adult boars and once a week for young boars (around 1 year old), which can fix the sperm collection frequency for each boar.
3、 Semen examination
（1） The principle of precision testing for boars is as follows:
1. All male pigs in use must have their semen checked once a month.
2. Male pigs that fail the sperm test cannot be used. If there are not enough male pigs, artificial insemination should be used
3. All reserve boars must pass the semen examination before they can be put into use.
4. Regarding the re inspection of unqualified boars, please follow the "Five week Four time Precision Inspection Method" for re inspection.
（2） Five week and four time precision inspection method
1. Male pigs that fail the fine inspection will be retested 7 days later.
2. Male pigs that fail the re inspection will have their semen collected 10 days later, followed by another 4 days for semen collection and inspection.
3. Those who still fail will have their semen collected 10 days later and undergo a fourth examination 4 days later.
After five consecutive weeks of four sperm tests, it is recommended to eliminate male pigs that have consistently failed. If they pass the mid-term test, they can be used according to their semen condition.
（3） Interim Standard for Complete Semen Examination of Boars
Excellent: Semen volume above 250ML, vitality above 0.8, density above 300 million/ML, abnormality rate below 5%, normal sensory perception.
Good: Semen volume above 150ML, vitality above 0.7, density above 200 million/ML, abnormality rate below 10%, normal sensory perception.
Qualified: Semen volume above 100ML, vitality above 0.6, density above 80 million/mL, abnormality rate below 18% (set at 20% in summer), normal sensory perception.
Unqualified: Semen volume below 100ML and density below 80 million/ML, vitality below 0.6, abnormality rate above 18% (set at 20% in summer), normal sensory perception. If any of the above four conditions are met, it will be rated as unqualified.
4、 Scope of Laboratory Functions
1. Ensure that all male pigs in use on the production line undergo at least one precision inspection per month. Non compliant male pigs should be retested according to the "Five Week Four Precision Inspection Method".
2. Make a semen plan to ensure the normal supply of semen throughout the venue and ensure the quality of semen.
3. At least once a month, report the semen condition of all male pigs in the field to the director.
4. Responsible for collecting weekly reports on artificial insemination and binding them once a month.
5. Keep records of the consumption of items and semen in artificial insemination, and prepare a procurement plan for commonly used consumables in advance and submit it to the field manager.
6. Responsible for the cleanliness and hygiene of the laboratory, daily care of all equipment, and simple maintenance.
7. Responsible for guiding and supervising the production line sperm injection work.
8. Analyze and summarize the results of artificial insemination, promptly identify problems, and report unresolved issues to superiors in a timely manner.
5、 Dilution and dilution ratio of semen
The dilution ratio needs to be determined before dilution. The dilution factor is determined based on the density of sperm in semen and the number of sperm per milliliter of semen after dilution. After dilution, pig semen is required to contain 100 million sperm per milliliter. If the density is not determined, the dilution ratio for local varieties is generally 0.5-1 times, and for introduced varieties it is 2-4 times.
Semen dilution should be carried out as soon as possible after semen extraction, and the temperature of semen and diluent must be adjusted to be consistent. Generally, semen and diluent are diluted at the same temperature (30 ℃).
6、 Preservation of Semen
In order to prolong the survival time of sperm, expand the scope of semen use, and facilitate long-distance transportation, diluted semen needs to be stored.
① Room temperature storage: Under room temperature conditions of 15-20 ℃, use the weakly acidic environment of diluent to inhibit sperm activity and reduce energy consumption. The antibiotics in the diluent can inhibit microbial reproduction, reduce the harm to sperm, and preserve semen for about 3 days.
② Low temperature storage: Under conditions of 0-5 ℃, the vitality of sperm is inhibited, metabolic levels are reduced, energy consumption is reduced, and the survival time of sperm is prolonged. Under low-temperature storage, the temperature range of 10-0 ℃ is a dangerous temperature range for sperm. If semen rapidly drops from room temperature to 0 ℃, irreversible cold shock will occur in the sperm. Therefore, semen needs to undergo pre cooling equilibrium before being stored at low temperatures. The specific method is to cool down by 0.2 ℃ per minute and complete the entire cooling process in 1-2 hours. In addition, adding substances such as yolk and milk to the diluent can also enhance the cold resistance of sperm.
Under the condition of no ice source in rural areas, the following methods can be used to manufacture cold sources:
① Dissolve 40g of salt in 1500mL of cold water, add 400g of ammonium chloride, and place it in a wide mouthed thermos flask. The temperature can be lowered to around 2 ℃. If you want to maintain low temperature for a long time, add ammonium chloride again every 2 days.
② Dissolve 60g of urea in 100mL of cold water to cool it down to 5 ℃. If dissolved in ice water, it can be cooled to -5 ℃.
③ Wrap and tie the storage bottle in a plastic bag, and secure the bag opening. Place the plastic bag for storing semen in a container such as a bamboo tube or basket, and then hang the container at the bottom of the well for storage.
7、 Vas deferens
At the beginning, pig farms that used artificial insemination mostly adopted the method of one local crossing and two artificial insemination, gradually transitioning to full artificial insemination.
Sperm motility must be checked before ejaculation, and semen below 0.6 must be discarded resolutely.
The specific operating procedures of the production line are:
1. Prepare the vas deferens, 0.1% KMnO4 disinfectant, clean water, cloth, semen, scissors, needles, dry cleaning towels, etc.
First, clean the area around the external genitalia and tail root of the sow with disinfectant, then rinse off the disinfectant with mild water and dry the external genitalia.
2. Drive the trial male pigs to the waiting mother pig pen (note: after estrus identification, the male and female pigs will no longer meet until they are fertilized), so that the female pig can have oral and nasal contact with the male pig during insemination. After transferring a few female pigs, replace one male pig to increase the excitement of the male and female pigs.
3. Take out a non contaminated disposable vas deferens from the sealed bag (do not touch the front 2/3 of it with your hands), and apply non-toxic lubricating oil to the front end.
4. Insert the vas deferens diagonally upwards into the reproductive tract of the sow, and when resistance is felt, apply slight force until the front end is locked by the cervix (gently pulling back will not move).
5. Retrieve semen from the storage container and confirm that the label is correct.
6. Be careful to mix the semen, cut off the bottle mouth, connect the semen bottle to the vas deferens, and start the sperm injection.
7. Gently press the vas deferens bottle to confirm that semen can flow out. Use a needle to make a small hole at the bottom of the bottle, massage the sow's breasts, external genitalia, or back to create negative pressure in the uterus to absorb semen. Never squeeze semen into the sow's reproductive tract.
8. By adjusting the height of the vas deferens bottle, the ejaculation time can be controlled. Generally, it takes 3-5 minutes to complete the infusion, and the fastest time should not be less than 3 minutes to prevent rapid suction and backflow.
9. After losing, while preventing air from entering the sow's reproductive tract, fold the posterior end of the vas deferens and insert it into the vas deferens bottle, allowing it to remain in the reproductive tract and slowly slide down. Collect the vas deferens and flush the vas deferens before leaving work.
10. After losing a sow, immediately register the mating record and score truthfully.
Additional explanation:
1. After being taken out of the 17 ℃ freezer, semen does not need to be heated up and can be directly used for insemination.
2. Selection of vas deferens: Sponge head vas deferens is used for multiparous sows, while pointed head vas deferens is used for reserve sows. Before insemination, the sponge head should be checked for looseness.
3. The time interval between two sperm injections is 8-12 hours.
4. During the process of ejaculation, if there is a situation of pulling urine, it is necessary to replace the vas deferens in a timely manner. After pulling feces, it is not allowed to push the vas deferens into the reproductive tract again.
5. Individual sows that still show stable estrus 12 hours after three rounds of insemination may undergo an additional artificial insemination.
6. The method of full artificial insemination: the sow will be treated 8-12 hours after experiencing a 'standing reaction'Administer a single intramuscular injection of 20IU oxytocin, and perform * insemination after 3-5 minutes, with a second and third insemination interval of 8-12 hours.
8、 Tracking and analysis of vasectomy procedure
The purpose of vas deferens scoring is to truthfully record the specific situation during vas deferens, so that in the future, when there is a mismatch or low birth rate, the cause can be identified, corresponding countermeasures can be formulated, and improvement measures can be made in future work. The vas deferens scoring is divided into three aspects and three levels:
Standing estrus: 1 point (poor), 2 points (some movement), 3 points (almost no movement).
Locking degree: 1 point (not locked), 2 points (loosely locked), 3 points (continuously firmly locked).
Degree of reflux: 1 point (severe reflux), 2 points (some reflux), 3 points (almost no reflux).
In order to make the sperm insemination scores comparable, all sperm inseminators should be scored according to the same criteria, and a single sperm inseminator should complete all the sperm insemination of a sow several times and truthfully report the scores.
Specific scoring method: For example, if a sow has obvious standing reflex, almost no movement, continuous firm locking, and some backflow, then the insemination score for this breeding is 333, and there is no need for it.
Through the report, it is possible to statistically analyze the proportion of timely breeding, the production performance of each boar, the technical operation level of each vas deferent, and the relationship between estrus and vas deferens scores.

9、 Diluted semen preparation technology for pigs
With the development of pig farming production and the advancement of industrialization process. People's understanding of the importance of artificial insemination in pigs is becoming increasingly profound. In modern pig production and breeding work, artificial insemination is becoming a very important production method. In recent years, the emergence of large-scale and highly intensive modern animal husbandry has further promoted the application and development of artificial insemination. The dilution, preservation, and application of pig semen have been promoted and applied in various provinces and regions throughout the 1970s and 1980s, and have achieved good results. The following is a brief introduction to the dilution and preparation technology of frozen semen for pig artificial insemination, for reference by colleagues.

（1） Preparation of pig semen diluent
There are many types of commonly used pig semen diluents, and their formulas include the following:
1. Milk powder diluent: 9g milk powder, 100mL distilled water.
2. Diluted glucose solution: 5g glucose, 0.5g sodium citrate, 100mL distilled water.
3. Diluted solution of "Kafu": 6g glucose, 0.35g sodium citrate, 0.12g sodium bicarbonate, 0.37g sodium ethylenediaminetetraacetic acid, 30000 IU penicillin, 100000 IU streptomycin, 100mL distilled water.
4. Ammonia egg solution: 3g of amino acetic acid and 100mL of distilled water are used to prepare the base solution. 70mL of the base solution is mixed with 30mL of yolk.
5. Glucose solution: 5g glucose, 0.3g sodium citrate, 0.1g ethylenediaminetetraacetic acid, 100mL distilled water.
6. Grape lime carbon ethyl egg solution: 5.1g glucose, 0.18g sodium citrate, 0.05g sodium bicarbonate, 0.16g ethylenediaminetetraacetic acid, 100mL distilled water, prepare a base solution, add 3mL yolk to 97mL base solution.
The dosage of antibiotics for the above diluents, except for "Kafu", is 1000 lu/mL penicillin and 1000 μ g/mL dihydrostreptomycin.

（2） Preparation of three commonly used diluents for external use

1. BL-1 solution (USA): Glucose 2.9%, Sodium Citrate 1%, Sodium Bicarbonate 0.2%, Potassium Chloride 0.03%, Penicillin 1000IU/mL, Dihydrostreptomycin 0.01%.
2. IVT solution (English): 0.3g glucose, 2g sodium citrate, 0.21g sodium bicarbonate, 0.04g potassium chloride, 0.3g aminobenzenesulfonic acid, 100mL distilled water. Mix and heat until fully dissolved. After cooling, introduce carbon dioxide for about 20 minutes to achieve a pH of 6.5.
3. Milk powder glucose solution (Japan): 3.0g skimmed milk powder, 9g glucose, 0.24g sodium bicarbonate, 0.2g α - amino-p-toluene sulfonamide hydrochloride, 0.4g sulfamethoxazole sodium, 200mL sterilized distilled water.

Taken from Veterinary Breeding Network