Method for improving Xinjiang Tianshan yak interspecific cross fertilization

Abstract

The invention relates to the technical field of livestock breeding, and particularly discloses a method for improving Xinjiang Tianshan yak interspecific hybridization fertilization, which comprises the following steps: cow selection, cow management, disease prevention, estrus regulation and control, vitamin ADE injection, thrombus removal and cloprostenol sodium injection, estrus identification, three-time artificial insemination, gonadorelin injection, pregnancy test, miscarriage prevention and post-hybridization management. According to special physiological characteristics and interspecific isolation problems of yaks in a high-altitude, cold and oxygen-deficient environment, the estrus rate and conception rate of the yaks are improved through environment selection, season regulation and control, male parent screening and scientific cow management, and the long-term problem that the interspecific hybridization conception rate of the yaks is low is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of animal husbandry, and in particular relates to a method for improving interspecific hybridization conception of Xinjiang Tianshan yaks. Background Art

[0002] Xinjiang Tianshan Yaks live in the Tianshan Mountains at an altitude of about 3,000 meters all year round. The high altitude, thin air, low atmospheric pressure, strong ultraviolet rays, changeable climate, and large temperature differences have cultivated the Tianshan Yaks' special physiological functions and appearance characteristics in the harsh environment of high cold and hypoxia. Long-term grazing life also makes yaks wild and difficult to approach. The ability to adapt to harsh environments in the plateau ecological environment is stronger than other animals. However, due to the "self-breeding and self-feeding" in groups, the Xinjiang Tianshan Yaks have been inbred and the breed has degenerated. The disease resistance, production performance, and fertility have seriously degenerated, which is mainly manifested in small physique, light weight, low fertility, and an average of one litter every 2-3 years, with low economic value. In order to change this situation, exogenous blood is introduced to carry out interspecific hybridization of yaks, thereby improving the performance of Xinjiang Tianshan Yaks.

[0003] As a special breed of livestock, yaks have long lived in the cold, oxygen-sparse environment of high altitudes in the Tianshan Mountains. Affected by the natural environment, special physiological characteristics, different individual physiques, and especially interspecies isolation, the conception rate of interspecies hybridization of yaks has been low for a long time, resulting in slow progress in the utilization of yak germplasm resources and yak breed improvement. Summary of the invention

[0004] The object of the present invention is to provide a method for improving interspecific hybridization conception of Xinjiang Tianshan yaks, so as to solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A method for improving interspecific hybridization conception of Xinjiang Tianshan yaks comprises the following steps:

[0007] S1. Cow selection:

[0008] The selected cows are aged over 6 years, with 2 or more parities, healthy cows with no history of infertility or abortion, and all brucellosis tests are negative. The selected cows are also body-shaped, with the height of the cow not less than 110 cm, the oblique length of the body not less than 120 cm, the chest circumference not less than 140 cm, the tube circumference not less than 15 cm, and the weight greater than 200 kg.

[0009] S2. Cow management

[0010] Before mating, starting from the birth of calves in May, the selected yaks will be fed artificially to fatten them up, and the bulls will be separated for epidemic prevention, quarantine and purification. In May, the mating cattle will be immunized against foot-and-mouth disease. Those that need to be immunized against anthrax and bovine leukopenia can be immunized in batches during this period. Blood will be collected during the immunization, and each yak will be quarantined for brucellosis. The positive cattle will be eliminated.

[0011] S3. Disease prevention:

[0012] Use ultrasound to check the uterine environment of the yaks. If inflammation is found in the uterus, timely treatment will be given; if there is no inflammation, preventive medication will be used.

[0013] S4. Regulating estrus:

[0014] Artificial estrus regulation began in mid-to-late July. Each cow was given a progesterone vaginal plug. Through body absorption, the progesterone concentration in plasma was increased, and the luteal phase was artificially delayed, thereby inhibiting the estrus and ovulation of the yaks. After the vaginal plug was buried, each cow was injected with gonadotropin (3 ml / head) to prevent the ovarian function of the yaks from being dormant.

[0015] S5. Injection of vitamin ADE

[0016] On the sixth day after the plug was buried, each yak was injected with 10 ml of vitamin ADE to prevent ADE deficiency in yaks;

[0017] S6. Remove the thrombus and inject cloprostenol sodium

[0018] On the 7th day, the embolus was removed. The tail of the release agent was grasped and slowly pulled out and placed in a waste bag for centralized disposal. While removing the embolus, 5 ml of cloprostenol sodium was injected simultaneously.

[0019] S7. Estrus identification:

[0020] Observe whether the yaks have any mounting behavior, whether the vulva is swollen and to what extent, and whether there is a small amount of transparent thin mucus flowing out;

[0021] S8, 3 times artificial insemination:

[0022] Starting from the second day after the plug is removed, rectal insemination is performed for each cow three times, once a day, for three consecutive days, with each session separated by 12-24 hours. The insemination site is deep in the uterine horns on both sides.

[0023] S9. Gonadorelin injection:

[0024] After each insemination, each cow was injected with 3 ml of gonadorelin. The gonadorelin was injected at 3 ml per cow on the first day of plug implantation and was injected at 3 ml per cow each time during insemination on the 8th, 9th and 10th days after plug removal.

[0025] S10. Pregnancy test:

[0026] Use B-ultrasound combined with rapid pregnancy test strips to test 42 days after mating. For cows that did not become pregnant after the first artificial insemination, use B-ultrasound estrus test. For cows that did not become pregnant, perform the second artificial insemination or select the group for natural mating outside to prevent empty foetuses.

[0027] S11, tire protection:

[0028] Inject 2 ml of gonadorelin per cow to the detected pregnant cows and non-pregnant cows in estrus;

[0029] S12. Post-breeding management:

[0030] Bulls must be strictly isolated and are prohibited from mixing with other groups. The isolation period is 3-5 months or during the entire pregnancy period. Choose pastures with abundant water and grass and flat terrain for grazing. Do a good job of disease prevention and immunization. Grazing is prohibited in extreme weather. At the same time, non-pregnant yaks must be removed from the herd.

[0031] Preferably, the body characteristics in S1 include but are not limited to cows with well-proportioned bodies, neat body hair, bright eyes, strong legs, and strong climbing ability.

[0032] Preferably, the drug for treating uterine inflammation in S3 is penicillin and streptomycin (double antibiotic), and the therapeutic dosage is: 1.6 million units of penicillin and streptomycin / head, once every other day, 2-3 times / head for one course of treatment; the preventive dosage is 800,000-1 million units / head, once / head.

[0033] Preferably, the S4 progesterone vaginal suppository is specifically a progesterone vaginal sustained-release agent, and the placement method comprises the following steps:

[0034] Rinse the vaginal inserter with a neutral, non-irritating disinfectant, immerse the front of the vaginal inserter in veterinary vaginal lubricant, put the progesterone releaser (vaginal plug) into the vaginal inserter, grab the tail and wipe the vulva with toilet paper, insert the vaginal inserter containing the progesterone releaser slightly upward into the vulva and push it into the front of the vagina, hold the vaginal inserter wrench to push out the progesterone releaser, take out the vaginal inserter, let the two wings of the corrosion inhibitor open in the vagina, and the tail leaks out of the vulva.

[0035] Preferably, the estrus identification in S7 includes a rectal examination method, in which a hand is inserted into the rectum to feel the size and development status of the follicles on the ovaries. The size is about 0.5-0.75 cm in the early stage and 1-1.5 cm in the later stage. There is a depression on the surface of the ovary after ovulation.

[0036] Preferably, the artificial insemination in S8 includes the following steps: quickly taking out a frozen sperm from the liquid nitrogen tank and placing it in a water temperature container at 32-38°C, dissolving in water for 30-45 seconds, wiping the moisture off the straw wall with toilet paper, cutting off 1.2-1.5 cm of the sealed end of the thin tube, and placing the cut thin tube flat into the insemination gun → inserting the insemination gun with the thin tube into the insemination outer sleeve, cleaning the vulva with toilet paper, holding the rectum with one hand, and holding the insemination gun with the other hand, inserting it obliquely upward from the vulva into the deep part of the uterine horn on one side, inseminating half of it, and then inserting it into the other side to inseminate the other half, taking out the insemination gun and the holster, and putting the holster into a waste bag for centralized treatment, and selecting Xinjiang brown cattle for the paternal sperm.

[0037] Preferably, during the pregnancy test in S10, 2-5 ml of blood is collected from the tail root of each cow at the same time as the B-ultrasound examination. After 10-20 minutes of serum precipitation, the blood is tested using a cattle early pregnancy test card. The detection method is as follows: take out the test paper card, place the sample hole and the detection port upward on a horizontal surface, absorb the serum with a pipette, place the dropper vertically on the sample hole "S", add 3 drops drop by drop, and let it stand for 20 minutes.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] In view of the special physiological characteristics of yaks in high altitude, cold and oxygen-sparse environment and the problem of inter-species isolation, the present invention improves the estrus rate and conception rate of yaks through environmental selection, seasonal regulation, paternal screening and scientific cow management, and solves the long-standing problem of low conception rate in inter-species hybridization of yaks.

[0040] Selecting Xinjiang brown cattle ensures that the hybrid offspring can adapt to the cold and oxygen-sparse environment, improves the survival ability, production performance and genetic quality of its offspring, and at the same time selects the maternal body shape to avoid dystocia problems, thereby greatly reducing the risk of dystocia and ensuring the health and safety of the cow and the fetus. At the same time, through strict cow selection, disease prevention, nutritional supplementation, scientific estrus regulation and drug assistance, the present invention significantly improves the physical condition and stress resistance of the cow during breeding, and promotes the healthy development of the fetus, providing a strong guarantee for the healthy development of the yak breeding industry. DETAILED DESCRIPTION

[0041] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0042] Embodiment 1:

[0043] A method for improving interspecific hybridization conception of Xinjiang Tianshan yaks comprises the following steps:

[0044] Interspecies hybridization should be carried out in the area where yaks live all year round in the Tianshan Mountains of Xinjiang, that is, an environment at an altitude of about 3,000 meters suitable for yaks to survive. The living environment of yaks should not be changed or they should be driven to low-altitude areas for breeding, so as to avoid changes in the physiological functions of yaks and survival stress, which will affect the effect of hybridization.

[0045] Artificial breeding season

[0046] The breeding is carried out in July and August when the grass is abundant and the temperature is high. At this time, the temperature in Tianshan District gradually rises, the rainfall increases, the pasture turns green quickly, the fatness of yaks improves, and the natural estrus rate is high, which is conducive to inter-species hybridization.

[0047] Artificial breeding of male parents and frozen semen

[0048] Given the small size of yaks, in order to avoid dystocia, it is generally not advisable to select large beef and dairy cows as male parents. Breeds of moderate size that are adapted to alpine grazing conditions and cold, oxygen-sparse environments, such as Xinjiang brown cattle, should be selected. At the same time, ensure that the sperm motility of bull frozen semen after thawing reaches above 0.40, and the effective sperm motility is above 10 million.

[0049] Select cows that are over 6 years old and have had more than 2 parities. Select healthy cows with no history of infertility or abortion. In addition to considering the number of parities of the cows, the calving interval of each parity should be recorded in detail. The calving interval should be kept within a certain range (such as 12-18 months) to ensure that the cows have enough recovery time and the ability to become pregnant again.

[0050] At the same time, assess the ease of delivery of the cows, give priority to cows that are easy to deliver, and select those that produce healthy and energetic calves.

[0051] At the same time, brucellosis testing is carried out to comprehensively check whether the cows have tuberculosis, brucellosis and other infectious diseases. These diseases not only affect the health of the cows, but may also affect their offspring through vertical transmission.

[0052] Carefully check the reproductive organs of the cows, especially the udder and uterus, to ensure that there is no history of reproductive system diseases such as mastitis and metritis. These diseases will affect the reproductive performance and milk production of cows.

[0053] Learn more about the hereditary diseases or adverse traits in the cow family, such as hereditary mastitis, limb and hoof diseases, etc. Avoid selecting cows with genetic defects to reduce the risk of disease in offspring.

[0054] Behavior observation: During the selection process, the behavior of the cows should be carefully observed. Cows that are lively, alert, and sensitive to changes in the surrounding environment usually have better nervous types and adaptability, and are more likely to adapt to new environments and breeding conditions.

[0055] Detailed body evaluation: Detailed evaluation of the cow's muscle development, bone structure, udder development, etc. Select cows with well-developed muscles, strong bones, well-developed udders and neatly arranged nipples, which are usually associated with high milk production and good reproductive performance.

[0056] Dynamic monitoring of fatness: Regularly evaluate the fatness of cows and adjust feeding management strategies based on the evaluation results. Too thin a cow will affect its breeding success rate and postpartum recovery ability, while too fat a cow may cause dystocia and postpartum diseases. Therefore, the cow's fatness should be kept moderate.

[0057] Standardization of body measurement: clarify the specific location and tool usage for measuring height, oblique length, chest circumference and tube circumference to avoid misjudgment due to measurement errors. The body shape characteristics are that the height of the cow is not less than 110cm; the oblique length is not less than 120cm; the chest circumference is not less than 140cm; the tube circumference is not less than 15cm, and the weight is greater than 200kg.

[0058] Check and record the production performance data of cows in detail, including milk production, milk fat percentage, reproductive efficiency and other indicators.

[0059] Genetic evaluation: Genetic evaluation is performed to assess the genetic potential of cows using techniques such as genetic markers or genomic selection.

[0060] By the end of April or earlier, develop a detailed pre-breeding management plan, including specific timetables and responsibilities for supplementary feeding, fattening, epidemic prevention, quarantine and purification.

[0061] Ensure that all participants are aware of their respective responsibilities and receive necessary training. Re-feeding and fattening and bull isolation: Starting from the birth of calves in May, the selected yaks will be immediately fed artificially to fatten them, using high-quality feed to ensure that the yaks recover quickly.

[0062] At the same time, separate the bulls from the cows to avoid unnecessary mating and energy consumption, and to prepare them fully for breeding.

[0063] Integrate immunization procedures: Concentrate immunizations for foot-and-mouth disease, anthrax, bovine sphincter and other vaccines in May to reduce the labor intensity and stress response of multiple operations.

[0064] Blood collection and quarantine are carried out simultaneously: while immunizing, blood is collected from each cow for brucellosis quarantine to ensure that positive cows are eliminated in time and reduce the risk of disease transmission.

[0065] Use highly effective vaccines and detection technologies: Choose proven highly effective vaccines and adopt rapid and accurate detection technologies to improve immunization effectiveness and quarantine accuracy.

[0066] After the positive cattle tested out in quarantine are promptly eliminated, the herd is thoroughly disinfected and purified, including environmental disinfection and equipment disinfection, to eliminate residual pathogens.

[0067] During the entire process, detailed records of the immunization, quarantine and purification treatment of each yak are kept and a health file is established.

[0068] Regularly monitor the health of yaks to detect and handle abnormal situations in a timely manner.

[0069] Feed and nutrition management: Adjust feed formula according to the nutritional needs of yaks to ensure that yaks get balanced nutrition. Monitor the weight and body condition of yaks and adjust the feeding amount in time.

[0070] Training and communication: Regularly train breeding personnel to improve their professional skills and awareness of epidemic prevention. Strengthen communication and cooperation with veterinarians, nutritionists and other professionals to ensure the scientificity and effectiveness of management plans.

[0071] Regular ultrasound examinations are not limited to detecting inflammation, but should also focus on the overall health of the uterus, including the thickness and morphology of the endometrium and whether there are abnormal structures.

[0072] Yaks found to have uterine inflammation should be isolated and treated immediately to prevent the inflammation from spreading and affecting the entire herd. After the treatment, an ultrasound examination should be performed again to confirm whether the inflammation has completely subsided.

[0073] The drug for treating uterine inflammation is penicillin-streptomycin (double antibiotic). The therapeutic dosage is: 1.6 million units of penicillin-streptomycin / head, once every other day, 2-3 times / head for one course of treatment; the preventive dosage is 800,000-1 million units / head, once / head.

[0074] For yaks that are not inflamed, in addition to preventive medication, feeding management should be strengthened, the cowshed should be kept clean and hygienic, and the breeding of pathogens such as bacteria and viruses should be reduced.

[0075] Uterine examination equipment includes GDF-C70 wireless cow ultrasound machine, Kaixin MSU1 / MSU2, etc. to regulate estrus and optimize reproduction

[0076] Before artificial estrus regulation, a comprehensive health check should be conducted on yaks to ensure that they are in a suitable state for estrus regulation. When burying progesterone vaginal suppositories, the operation should be standardized to avoid unnecessary harm to yaks. At the same time, the position and status of the vaginal suppository should be checked regularly to ensure that it works effectively.

[0077] When injecting gonadorelin, the dosage should be accurately controlled and the yak's reaction should be carefully observed. If there is any abnormality, it should be handled in time. Each yak is injected with 3ml of gonadorelin (gonadotropin).

[0078] Injection of vitamin ADE: Before injecting vitamin ADE, it should be confirmed whether the yaks are actually suffering from ADE deficiency to avoid blind use of medication.

[0079] The injection amount of vitamin ADE should be adjusted appropriately according to factors such as the yak's weight, age and nutritional status.

[0080] Removing the embolism and injecting cloprostenol sodium: When removing the embolism, ensure that the operation is gentle and quick to avoid irritation or injury to the yaks. When injecting cloprostenol sodium, the dosage should be accurately controlled and the reaction of the yaks should be carefully observed to ensure that the drug works effectively. On the 6th day after embolism, each yak was injected with 10ml of vitamin ADE.

[0081] The S4 progesterone vaginal suppository is specifically a progesterone vaginal sustained-release agent, and the placement method comprises the following steps:

[0082] Rinse the vaginal inserter with a neutral, non-irritating disinfectant, immerse the front of the vaginal inserter in veterinary vaginal lubricant, put the progesterone releaser (vaginal plug) into the vaginal inserter, grab the tail and wipe the vulva with toilet paper, insert the vaginal inserter containing the progesterone releaser slightly upward into the vulva and push it into the front of the vagina, hold the vaginal inserter wrench to push out the progesterone releaser, take out the vaginal inserter, let the two wings of the corrosion inhibitor open in the vagina, and the tail leaks out of the vulva.

[0083] When identifying estrus, in addition to observing the behavior of yaks, rectal examination and other methods should be combined to more accurately determine whether the yaks are in estrus. For yaks that are not obviously in estrus, multiple observations or examinations should be carried out to avoid misjudgment. The rectal examination method does not require the hand to reach into the rectum to feel the size and development of the follicles on the ovaries. In the early stage, it is about 0.5-0.75 cm, and in the later stage, it is 1-1.5 cm. After ovulation, the surface of the ovary is concave.

[0084] Before artificial insemination, the yaks should be thoroughly cleaned and disinfected to avoid infection. During insemination, the depth and position of the vas deferens insertion should be ensured to avoid damage to the yaks or affecting the fertilization effect. Artificial insemination includes the following steps: quickly take out a frozen sperm from the liquid nitrogen tank and place it in a water temperature container at 32-38°C, dissolve in water for 30-45 seconds, wipe the moisture on the pipette wall with toilet paper, cut off 1.2-1.5 cm of the cap of the capillary, put the cut capillary flat into the insemination gun, put the insemination gun with the capillary into the insemination outer sleeve, clean the vulva with toilet paper, hold the rectum with one hand, hold the insemination gun with the other hand, and insert it from the vulva obliquely upward into the deep part of the uterine horn on one side, inseminate half, and then insert it into the other side to inseminate the other half, take out the insemination gun and the holster, put the holster into a waste bag for centralized treatment, and the paternal sperm selects Xinjiang brown cattle.

[0085] After each insemination, the yak number, insemination time, insemination site and other information should be recorded in detail for follow-up tracking and management. When injecting gonadorelin after each insemination, the dosage should be accurate and the yak's reaction should be observed. If the yak is found to have an adverse reaction to gonadorelin or the effect is not good, the medication plan should be adjusted in time.

[0086] During pregnancy test, the quality of B-ultrasound and rapid pregnancy test paper should be ensured to be reliable and the operation should be standardized to avoid misjudgment. For non-pregnant yaks, artificial insemination or natural mating should be carried out again in time to improve the pregnancy rate. At the same time, the reasons for non-pregnancy should be analyzed and summarized so as to improve the breeding management work in the future. For pregnant yaks, feeding management should be strengthened to ensure that they can smoothly pass the pregnancy period and give birth to healthy calves. At the same time as the B-ultrasound examination, 2-5ml of blood is collected from the tail root of each cow. After 10-20 minutes after the serum is precipitated, it is tested with the cattle early pregnancy test card. The detection method is as follows: take out the test paper card, put the sample hole and the detection port facing up on the water table, use a pipette to absorb the serum, make the dropper vertical on the sample hole "S", add 3 drops drop by drop, let it stand for 20 minutes, and observe the results; Result judgment: 1. Positive Two red strips (T detection line, C quality control line) can be seen in the test window of the test paper card. Regardless of the depth of the line, it is judged as positive, indicating pregnancy. 2. Negative: A red stripe appears (C quality control line), which is judged as negative, indicating no pregnancy. 3. Invalid: No red stripe appears on the detection window quality control line (C), which is judged as invalid result.

[0087] In summary, the present invention has successfully overcome the problem of low conception rate in interspecific hybridization of yaks through a series of scientific and sophisticated measures, effectively optimized the genetic quality of yaks, improved the health level of cows and fetuses, significantly improved breeding efficiency, and provided strong support for the sustainable development and transformation and upgrading of the yak industry.

[0088] It will be appreciated that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but will be a routine task of design, fabrication, and production for those of ordinary skill having the benefit of this disclosure without undue experimentation.

[0089] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for improving interspecific hybridization conception of Xinjiang Tianshan yaks, characterized in that: The following steps are involved: S1. Cow selection: The selected cows are aged over 6 years, with 2 or more parities, healthy cows with no history of infertility or abortion, and all brucellosis tests are negative. The selected cows are also body-shaped, with the height of the cow not less than 110 cm, the oblique length of the body not less than 120 cm, the chest circumference not less than 140 cm, the tube circumference not less than 15 cm, and the weight greater than 200 kg. S2. Cow management: Before mating, starting from the birth of calves in May, the selected yaks will be fed artificially to fatten them up, and the bulls will be separated for epidemic prevention, quarantine and purification. In May, the mating cattle will be immunized against foot-and-mouth disease. Those that need to be immunized against anthrax and bovine leukopenia can be immunized in batches during this period. Blood will be collected during the immunization, and each yak will be quarantined for brucellosis. The positive cattle will be eliminated. S3. Disease prevention: Use ultrasound to check the uterine environment of the yaks. If inflammation is found in the uterus, timely treatment will be given; if there is no inflammation, preventive medication will be used. S4. Regulating estrus: Artificial estrus regulation began in mid-to-late July. Each cow was given a progesterone vaginal plug. Through body absorption, the progesterone concentration in plasma was increased, and the luteal phase was artificially delayed, thereby inhibiting the estrus and ovulation of the yaks. After the vaginal plug was buried, each cow was injected with gonadotropin (3 ml / head) to prevent the ovarian function of the yaks from being dormant. S5. Injection of vitamin ADE: On the sixth day after the plug was buried, each yak was injected with 10 ml of vitamin ADE to prevent ADE deficiency in yaks; S6. Remove the thrombus and inject cloprostenol sodium: On the 7th day, the embolus was removed. The tail of the release agent was grasped and slowly pulled out and placed in a waste bag for centralized disposal. While removing the embolus, 5 ml of cloprostenol sodium was injected simultaneously. S7. Estrus identification: Observe whether the yaks have any mounting behavior, whether the vulva is swollen and to what extent, and whether there is a small amount of transparent thin mucus flowing out; S8, 3 times artificial insemination: Starting from the second day after the plug is removed, rectal insemination is performed for each cow three times, once a day, for three consecutive days, with each session separated by 12-24 hours. The insemination site is deep in the uterine horns on both sides. S9. Gonadorelin injection: After each insemination, each cow was injected with 3 ml of gonadorelin. The gonadorelin was injected at 3 ml per cow on the first day of plug implantation and was injected at 3 ml per cow each time during insemination on the 8th, 9th and 10th days after plug removal. S10. Pregnancy test: Use B-ultrasound combined with rapid pregnancy test strips to test 42 days after mating. For cows that did not become pregnant after the first artificial insemination, use B-ultrasound estrus test. For cows that did not become pregnant, perform the second artificial insemination or select the group for natural mating outside to prevent empty foetuses. S11, tire protection: Inject 2 ml of gonadorelin per cow to the detected pregnant cows and non-pregnant cows in estrus; S12. Post-breeding management: Bulls must be strictly isolated and are not allowed to mix with other groups. The isolation period is 3-5 months or during the entire pregnancy period. Choose pastures with abundant water and grass and flat terrain for grazing; prevent disease immunization, prohibit grazing in extreme weather, and at the same time clear non-pregnant yaks out of the herd.

2. The method for improving interspecific hybridization conception of Xinjiang Tianshan yaks according to claim 1, characterized in that: The physical characteristics in S1 include but are not limited to cows with a well-proportioned body, neat fur, bright eyes, strong legs, and strong climbing ability.

3. The method for improving interspecific hybridization conception of Xinjiang Tianshan yaks according to claim 1, characterized in that: The drug for treating uterine inflammation in S3 is penicillin-streptomycin (double antibiotic), and the therapeutic dosage is: 1.6 million units of penicillin-streptomycin / head, once every other day, 2-3 times / head for one course of treatment; the preventive dosage is 800,000-1 million units / head, once / head.

4. The method for improving interspecific hybridization conception of Xinjiang Tianshan yaks according to claim 1, characterized in that: The S4 progesterone vaginal suppository is specifically a progesterone vaginal sustained-release agent, and the placement method comprises the following steps: Rinse the vaginal inserter with a neutral, non-irritating disinfectant, immerse the front of the vaginal inserter in veterinary vaginal lubricant, put the progesterone releaser (vaginal plug) into the vaginal inserter, grab the tail and wipe the vulva with toilet paper, insert the vaginal inserter containing the progesterone releaser slightly upward into the vulva and push it into the front of the vagina, hold the vaginal inserter wrench to push out the progesterone releaser, take out the vaginal inserter, let the two wings of the corrosion inhibitor open in the vagina, and the tail leaks out of the vulva.

5. The method for improving interspecific hybridization conception of Xinjiang Tianshan yaks according to claim 1, characterized in that: The estrus identification in S7 includes a rectal examination method, in which the hand is inserted into the rectum to feel the size and development status of the follicles on the ovaries. The size is about 0.5-0.75 cm in the early stage and 1-1.5 cm in the later stage. There is a depression on the surface of the ovary after ovulation.

6. The method for improving interspecific hybridization conception of Xinjiang Tianshan yaks according to claim 1, characterized in that: The artificial insemination in S8 comprises the following steps: quickly taking out a frozen sperm from a liquid nitrogen tank and placing it in a water temperature container of 32-38°C, dissolving in water for 30-45 seconds, wiping the moisture off the straw wall with toilet paper, cutting off 1.2-1.5 cm of the sealed end of the thin tube, placing the cut thin tube flat into the insemination gun, placing the insemination gun with the thin tube into the insemination outer sleeve, cleaning the vulva with toilet paper, holding the rectum with one hand, and holding the insemination gun with the other hand, inserting it obliquely upward from the vulva into the deep part of the uterine horn on one side, inseminating half of it, and then inserting it into the other side to inseminate the other half, taking out the insemination gun and the holster, and putting the holster into a waste bag for centralized treatment, and the paternal sperm selects Xinjiang brown cattle.

7. The method for improving interspecific hybridization conception of Xinjiang Tianshan yaks according to claim 1, characterized in that: During the B-ultrasound examination in the S10 pregnancy test, 2-5 ml of blood is collected from the tail root of each cow. After 10-20 minutes of serum precipitation, the blood is tested using a cow early pregnancy test card. The detection method is as follows: take out the test paper card, place the sample hole and the detection port facing up on a horizontal surface, absorb the serum with a pipette, place the dropper vertically on the sample hole "S", add 3 drops drop by drop, and let it stand for 20 minutes.