Method for improving reproduction rate of Tibetan sheep through management method

Abstract

The invention provides a method for improving the reproduction rate of Tibetan sheep through a management method. The method comprises the steps of 1, improving the efficient reproduction rate of ewes, 2, improving the nutrition level of the ewes, 3, conducting nutrition regulation and control on the ewes and 4, conducting disease prevention and control. According to the method, the reproduction rate of the Tibetan sheep is increased from the management method from the whole.

Description

Technical Field

[0001] The invention belongs to the technical field of sheep breeding, and in particular relates to a method for improving the reproduction rate of Tibetan sheep through a management method. Background Art

[0002] In the alpine pastoral areas of northwest Sichuan, most herders still raise Tibetan sheep in a full grazing manner. Under the full grazing breeding method, ewes can only produce one litter a year, and the production capacity is low, which seriously restricts the development of the sheep industry.

[0003] Tibetan sheep breeding is one of the pillar industries in the northwestern Sichuan pastoral area, but the Tibetan sheep breed is primitive, with low productivity, a reproduction rate of only about 10.5%, and a high mortality rate, especially in the seven-month dry grass season in winter and spring; the weaning time is long, and Tibetan sheep lambs can only be weaned at 5-6 months old. The time to market is long, and it usually takes 18-24 months from birth to market, and the market rate is only about 60%.

[0004] Zhu Xinshu, Wang Hongbo, Bao Pengjia, Li Shihong, Chen Shenghong, Xia Yongqi, Wang Haicheng, and Zhang Gong published a paper titled "Study on Early Supplementary Feeding Cultivation Model of Tibetan Sheep Lactating Lambs" in the journal "Anhui Agricultural Science" in 2015. The paper recorded the use of a single factor design to explore the early supplementary feeding cultivation model of Tibetan sheep lactating lambs. Under the same conditions of grazing and supplementary feeding of roughage, the supplementary feeding effect of milk replacer + complete feed on Tibetan sheep lactating lambs was significantly better than that of corn or complete feed alone, and the difference in daily weight gain was significant (P < 0.05) or extremely significant (P < 0.01). Under effective supplementary feeding conditions, Tibetan sheep lambs grow and develop rapidly, with an early average daily weight gain of 140-160g / d, and a lamb survival rate of 93.75%.

[0005] However, the above-mentioned supplementary feeding method only increases nutrition for lactating sheep, and the comparison is only with no supplementary feeding. It does not consider the growth characteristics of Tibetan sheep as a whole and is not convincing. Therefore, there is an urgent need for a method to improve the reproduction rate of Tibetan sheep starting from the management method. Summary of the invention

[0006] The purpose of the present invention is to solve the defects of the above-mentioned prior art and provide a method for improving the reproduction rate of Tibetan sheep through a management method.

[0007] The present invention adopts the following technical solution:

[0008] A method for improving the reproduction rate of Tibetan sheep through a management method comprises the following steps:

[0009] Step 1. Improve the efficient reproduction rate of ewes

[0010] Step 100. Selection of male and female parents

[0011] The rams are selected from excellent breeds such as White Suffolk Sheep and Hu Sheep, which are strong, have obvious breed characteristics, well-developed testicles, strong virility, and good semen quality. The ewes are selected from Tibetan sheep, which are large, have good maternal instincts, and have good lactation and breastfeeding performance.

[0012] Step 101. Increase the proportion of breeding ewes of suitable age and implement frequent lambing

[0013] Increase the proportion of ewes in the flock, the proportion of ewes in the flock is increased to 70%, the proportion of ewes of appropriate age (2-5 years old) reaches more than 50%, and lambing is frequent.

[0014] Step 102. Breeding at the right time

[0015] In the northwest of Sichuan, ewes are bred in June and July. The breeding time for ewes is in the middle and late estrus period, that is, 18-24 hours after the onset of estrus.

[0016] Step 103. Weaning at the right time

[0017] Lambs are weaned at one time.

[0018] S1031. Lamb weaning precautions

[0019] After weaning, feed high-quality forage: fresh grass or legume hay supplemented with mixed concentrates. Provide sufficient clean drinking water.

[0020] S1032. Management during weaning adaptation period

[0021] The lambs are in the 5-7 day adaptation period after weaning. At the beginning, they are still provided with the same feed type, with roughage mainly consisting of high-quality grass and hay. The proportion of concentrate feed gradually increases.

[0022] Step 104. Promote estrus after weaning

[0023] S1041. Induce estrus

[0024] Inducing estrus is achieved through early weaning of lambs, hormone treatment and biological stimulation.

[0025] S10411. Early weaning of lambs

[0026] First, the lambs are weaned early, and then the ewes are treated with progesterone for 10 days. After stopping the drug, pregnant mare serum gonadotropin is injected.

[0027] S10412. Biological stimulation

[0028] Including changes in environmental conditions and sex hormones. Changes in environmental conditions can shorten the daylight hours by adjusting the light cycle, thus achieving estrus and ovulation. Sex hormones can bring the breeding season forward by introducing rams into the ewe flock before the normal breeding season begins, thus shortening the interval from postpartum to ovulation.

[0029] S1042. Synchronous estrus

[0030] One is to administer progestogen to a group of ewes to be treated at the same time to inhibit the growth and development of ovarian follicles and estrus, and then stop the drug at the same time after a certain period of time, which will cause simultaneous estrus. Another way is to use another type of hormone with completely different properties to inhibit the corpus luteum, accelerate its regression, shorten the luteal phase, reduce progesterone levels, thereby promoting the release of pituitary gonadotropin and causing the estrus to come earlier.

[0031] The solution is as follows:

[0032] S10421. Vaginal sponge method

[0033] Place a sponge soaked with progesterone at the cervix for 10-14 days, and inject 400-500 international units of pregnant mare serum gonadotropin after stopping the drug. Estrusity will begin after about 30 hours, and insemination will be performed once on the day of estrus and the next day. Common types and doses of progesterone are: progesterone 150-300 mg, medroxyprogesterone 50-70 mg, megestrol acetate 80-150 mg, 18-methyl-norethindrone 30-40 mg, and fluprogesterone 20-40 mg.

[0034] S10422. Oral administration

[0035] Mix a certain amount of the drug evenly into the feed every day and feed it continuously for 12-14 days. The drug dosage is about 1 / 10-1 / 5 of the vaginal sponge method. On the day of the last oral medication, 400-750 international units of pregnant mare serum gonadotropin should be injected intramuscularly.

[0036] S10423. Prostate hormone method

[0037] Prostaglandin F2a or its analogues are infused into the uterus or injected intramuscularly at a certain dose after the end of estrus, which can induce estrus in ewes within 2-3 days.

[0038] S1043. Supplemental feeding to stimulate estrus

[0039] Improve the diet composition one month before breeding

[0040] Step 2. Improve the nutritional level of ewes

[0041] Step 201. When the energy level is appropriate, the sheep will begin to estrus when their weight reaches about 35%-70% (6-8 months old) and 60% (5-10 months old) of their adult weight. When the energy level is insufficient, the growth is slow and the initial stage is delayed; when the energy level is high, the first estrus is advanced.

[0042] Step 202. Relationship between energy and ovulation and lambing rate

[0043] Practice has shown that it is best to keep the ewe's body condition at an above-average level during breeding. For extremely thin ewes, improving the feeding nutrition level before breeding, increasing the feed intake, supplementing the feed with compound feed, and adding alfalfa hay can improve the body condition and increase the ewe's ovulation rate.

[0044] Step 203. Short-term feeding to improve nutrition

[0045] Experiments have shown that the reproductive capacity of ewes is closely related to their weight. The heavier the weight of sheep of the same breed at the time of mating, the higher their reproductive capacity. The weight is determined by the nutritional level. It is estimated that for every 4.5kg increase in the weight of Merino before mating, the number of twin lambs can increase by 3%-5%. In Egypt, some people found that when the weight of ewes is lower than 40.9-45.5kg at the time of mating, the infertility rate will increase. According to data analysis, for every 1kg increase in the weight of sheep at the time of mating, the birth rate will increase by 2.1%.

[0046] Step 204. Sheep mineral supplementation

[0047] S2041. Calcium and phosphorus

[0048] Supplement calcium and phosphorus in the diet.

[0049] S2042. Selenium

[0050] Inject 6 mg of selenium and 272 I U of vitamin E into the ewes 4 weeks before mating.

[0051] S2043. Zinc

[0052] In the daily diet of breeding rams, add 0.5-1.0 mg of zinc sulfate per kilogram of body weight.

[0053] S2044. Magnesium

[0054] Feed a magnesium-supplemented diet.

[0055] S2045. Iodine

[0056] By supplementing with 0.3mg / kg iodized salt.

[0057] S2046. Vitamin A

[0058] Supplement vitamin A in the diet.

[0059] S2047. Vitamin E deficiency

[0060] Both ewes and rams were supplemented with vitamin E.

[0061] Step 3. Nutritional regulation of ewes

[0062] According to the physiological stage of the ewe, it is divided into three stages: empty period, pregnancy period and lactation period.

[0063] S301. Nutritional regulation of empty-pregnant ewes

[0064] Before mating, the empty-pregnant ewes should be fed with good feeding for a short period of time: that is, 10-15 days before mating, the ewes should be fed with 0.2 kg of concentrated feed per day and appropriate carrots or vitamins.

[0065] S302. Nutritional regulation of pregnant ewes

[0066] The first trimester is the 3 months after conception, and the baby is raised on pasture. The last trimester is the last 2 months of pregnancy, and the weight gain accounts for about 80% of the birth weight. The phosphorus and calcium needs should be increased by 40%-50%, and the calcium-phosphorus ratio should be 2 to 1. Adequate amounts of vitamin A and vitamin D.

[0067] S3021. Early pregnancy

[0068] Feed a certain amount of high-quality feed with high protein content. The ewes are required to maintain above medium fatness.

[0069] (1) During about one month of pregnancy, appropriate supplementary feed should be given.

[0070] (2) After 2 months of pregnancy, the amount of supplementary concentrate feed should be gradually increased. Pregnant sheep should be fed 2-3 times a day, with each sheep being fed 50-100 grams of mixed concentrate each time. The amount of concentrate feed for young ewes should also be appropriately increased.

[0071] (3) After three months of pregnancy, supplementary feeding should be done in small amounts and more frequently.

[0072] S3022. Late pregnancy

[0073] Increase dry matter requirement by 30%-40%, protein by 40%-60%, calcium and phosphorus by 1.2 times, and supplement vitamin A and vitamin D. Also provide high-quality hay and mixed feed. Add 0.4 kg of concentrate feed per day.

[0074] (1) After 4 months of pregnancy, during this stage of pregnancy supplementation, the amount of concentrated feed should be increased to about twice that of the early pregnancy, and the forage and supplementary concentrated feed should be fresh and diversified, with more tender green and juicy feed.

[0075] (2) About one month before delivery, control the amount of roughage fed and feed soft feed instead.

[0076] (3) About 10 days before delivery, reduce the amount of feed according to the ewe's appetite and digestive conditions.

[0077] (4) 2-3 days before delivery, for ewes with good physical condition, reduce the amount of feed in the original diet by 1 / 3-1 / 2; for relatively thin ewes, in addition to reducing the amount of roughage, you should also appropriately increase the amount of protein-rich lactation feed such as soybean cake and soybean dregs, as well as green and juicy laxative feed.

[0078] S3023. Nutritional regulation of lactating ewes

[0079] The main method of feeding is to feed in a shed, with high-quality tender grass and hay as the main feed. Clean drinking water is provided 3-4 times a day, and a small amount of salt and bran is added to the drinking water, or rice soup is fed to allow the sheep to drink freely. If the ewe has sufficient milk, no or less concentrate feed can be supplemented. When the lactation is insufficient, the ewe can be supplemented with green and juicy feed and an appropriate amount of concentrate feed. 15-20 days after the ewe gives birth, the supplementary feeding can be appropriately increased according to the amount of milk of the ewe. Generally, 0.3-0.5 kg of concentrate feed can be supplemented every day, and high-quality green feed should be fed as much as possible. In terms of management, attention should be paid to keeping the shed dry and clean, and regular manure removal and disinfection should be done.

[0080] S303. Precautions for breeding and management of breeding ewes:

[0081] (1) Carry out daily feeding and management according to feeding standards and breeding plans.

[0082] (2) During the non-breeding period, breeding ewes and reserve breeding ewes should be grouped and managed.

[0083] (3) Feeding and management of breeding ewes during the empty period. After weaning, the ewes are in a weak body condition and should be fed with green and roughage ad libitum. Each ewes should be fed with about 0.3 kg of concentrated feed per day to gain weight and regain strength.

[0084] (4) Feeding and management during pregnancy. The ewes’ demand for nutrients increases significantly during pregnancy (especially in the late pregnancy). Feeding and management should be strengthened, and complete concentrates (0.6-0.8kg / day per sheep) should be supplemented. If it is the dry grass season, a certain amount of silage should be supplemented to ensure their nutritional needs.

[0085] (5) In the late pregnancy, ewes should maintain a certain amount of exercise, about 4 hours a day. Try to avoid re-grouping in the late stage.

[0086] (6) Feeding management during the lactation period: In order to increase the milk production of ewes in the early stage of lactation, increase the supplementary feeding of concentrated feed and green feed.

[0087] (7) Keep the pens clean and conduct regular medicated baths, deworming and vaccinations.

[0088] (8) Regularly perform hoof trimming and other management.

[0089] S304. Recommended formula for supplementary feed for ewes

[0090] Concentrated feed formula for ewes

[0091] Referring to domestic and international mutton sheep nutrition standards and combining years of breeding experience, a basic supplementary feed formula for ewes has been developed. The amount of supplementary feed is determined according to the nutritional needs of ewes in different physiological periods and the nutritional indicators of basic ewe feed.

[0092] Every 1kg of feed is made of raw materials in the following weight ratio: 50% corn, 12% wheat, 12% soybean meal, 15% rapeseed meal, 3% salt, 3% baking soda, and 5% sheep premix.

[0093] Pregnancy

[0094] In the early stage of pregnancy (first 120 days of pregnancy), supplementary feeding is 0.3kg / d; in the late stage of pregnancy (last month of pregnancy), supplementary feeding is 0.6kg / d; no supplementary feeding is done 1-2 days before lambing.

[0095] Lactation

[0096] No supplementary feeding is done on the day of lambing. Depending on the physical condition of the ewe and the number of lambs, supplementary feeding is done from small amounts to large amounts within one week, reaching 0.5-0.8 kg / d per lamb. The amount is gradually reduced to 0.3 kg / d one week before weaning, and no supplementary feeding is done 1-2 days before weaning.

[0097] Empty period

[0098] No supplementary feeding is done on the first 1-2 days after weaning to encourage the ewes to recover their milk as soon as possible; then the supplementary feeding is gradually increased to 0.3kg / d over the next 3 days. On the 10th day after weaning, supplementary feeding is started at 0.5kg / d to promote estrus of the ewes.

[0099] Step 4. Disease prevention and control

[0100] S401. Strict disinfection

[0101] Commonly used disinfectants and their use:

[0102] Spraying 10%-20% lime milk on the ground, drainage ditches, feces, soil, etc. has a strong broad-spectrum disinfection effect. Spraying 5% or 10%-20% bleaching powder solution on sheep pens, sports venues, ditches, feces, etc., 5% solution can kill general pathogens, 10%-20% solution can kill spores. Spraying compound phenol on livestock and poultry pens, utensils, site excrement, etc., the general disinfectant liquid and water ratio is 1:300, when foot-and-mouth disease occurs, the liquid and water ratio is 1:200 disinfection, can effectively kill foot-and-mouth disease virus and other bacteria, fungi, viruses and other pathogenic microorganisms. Shelters, sites, drainage ditches, etc. can be sprayed with 0.5%-1.0% strong disinfectant, according to 1:200 or 1:100 aqueous solution, which has a significant killing effect on bacteria and viruses. Livestock houses, floors, and utensils can be sprayed with 1%-2% concentration of sodium hydroxide (caustic soda), which has a powerful killing effect on livestock houses, floors, and utensils contaminated with bacteria (Pasteurella, Salmonella, etc.) or viruses (foot-and-mouth disease, etc.).

[0103] S402. Regular deworming

[0104] Deworming is scheduled once in April and October each year. The drugs available are:

[0105] S403.Immunity

[0106] Commonly used immunization schemes and usage methods:

[0107] 20-30 days before pregnant ewes give birth, ewes are subcutaneously injected with 2ml lamb dysentery vaccine, and 3ml is injected every 10 days. The immunity period of ewes is 5 months, and lambs are passively immunized by eating milk to prevent lamb dysentery. In March-April and September-October every year, ewes are intramuscularly injected with 2ml / mouse and lambs are injected with 1ml / mouse foot-and-mouth disease AO-Asia I type three-in-one vaccine one month after giving birth and one month after the lambs are born to prevent foot-and-mouth disease. 15 days after the injection, 6 months of immunity are generated. Once in spring and autumn every year, according to the instructions for use, intramuscular injection of sheep triple defense quadruple vaccine is performed to prevent sheep rapid disease, sheep enterotoxemia, sheep anthrax, and sheep black disease. 6 months of immunity is generated 10-14 days after the injection. In February-March every year, 0.5ml of sheep pox chicken embryo attenuated vaccine is injected intradermally to prevent sheep pox disease. 6-10 days after the injection, the immunity period is maintained for 1 year.

[0108] Immunization considerations:

[0109] Furthermore, frequent lambing requires:

[0110] S1011. Select healthy, strong and well-nourished ewes, aged 2-6 years old.

[0111] S1012. Ewes must have good supplementary feeding conditions before and after calving.

[0112] S1013. Properly arrange the breeding time of ewes.

[0113] Further, regular deworming drugs include:

[0114] (1) To expel nematodes in the body: levamisole, albendazole, ivermectin, etc.

[0115] (2) Anti-tapeworms: closacil, praziquantel, dichlorophen sulfate or methotrexate (niclosamide), etc.

[0116] (3) To eliminate external parasites: injection of ivermectin or avermectin or bathing in 0.5-1% dichlorvos aqueous solution, etc.

[0117] Furthermore, matters that require attention during immunization include: (1) The interval between each vaccine injection and the interval between deworming is 7-10 days.

[0118] (2) It is best not to immunize against diseases that have not occurred locally, such as sheep pox, peste des petits ruminants, etc.

[0119] Beneficial effects of the present invention:

[0120] The method for improving the reproductive efficiency of Tibetan sheep adopted by the present invention can break the traditional breeding mode of Tibetan sheep giving birth once a year and shorten the breeding cycle by improving feeding management technology and breeding regulation under high-cold grazing conditions, so that the average production cycle of ewes reaches 262.53 days, which can meet the requirement of 4 births in 3 years. Thereby reducing the pressure on natural grasslands, alleviating the contradiction between livestock and grass, reducing winter and spring deaths, and finally achieving a win-win situation of increasing herders' income and protecting grassland ecological environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0121] Figure 1 It is a structural schematic diagram of the present invention. DETAILED DESCRIPTION

[0122] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention is described clearly and completely below. Obviously, the described embodiments are 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 creative work are within the scope of protection of the present invention.

[0123] like Figure 1 As shown, a method for improving the reproduction rate of Tibetan sheep through a management method of the present invention comprises the following steps:

[0124] Step 1. Improve the efficient reproduction rate of ewes

[0125] Step 100. Selection of male and female parents

[0126] The rams are selected from excellent breeds such as White Suffolk Sheep and Hu Sheep, which are strong, have obvious breed characteristics, well-developed testicles, strong virility, and good semen quality. The ewes are selected from Tibetan sheep, which are large, have good maternal instincts, and have good lactation and breastfeeding performance.

[0127] Step 101. Increase the proportion of breeding ewes of suitable age and implement frequent lambing

[0128] Whether the flock structure is reasonable has a great impact on the reproduction of sheep. Therefore, increasing the proportion of ewes in the flock is also an important measure to improve the reproductive capacity of sheep. Under normal circumstances, the proportion of ewes in the flock can be increased to 70%, and the proportion of ewes of appropriate age (2-5 years old) can reach more than 50%.

[0129] The frequent lambing system, also known as the intensive breeding system, is an efficient production system developed with the modern intensive production of meat sheep and fat lambs. Its meaning is: breaking the seasonal breeding characteristics of sheep, estrus and mating all year round, lambing evenly throughout the year, so that the breeding ewes can increase the carcass weight the most each year. Its characteristics are: maximizing the production performance of ewes, evenly supplying mutton to the market throughout the year, shortening the capital turnover period, improving equipment utilization and labor productivity, reducing costs, and facilitating intensive scientific management.

[0130] Frequent lambing of sheep, that is, giving birth to lambs three times in two years, or giving birth to lambs twice a year, giving birth to lambs four times in three years, giving birth to lambs five times in three years, etc. In order to ensure the smooth progress of intensive lambing, it is necessary to:

[0131] S1011. Choose healthy, strong and well-nourished ewes. The age of the ewes should be between 2 and 6 years old. Such ewes must also have well-developed breasts and relatively high milk production.

[0132] S1012. It is necessary to strengthen the feeding and management of ewes and their lambs. Ewes must have good supplementary feeding conditions before and after delivery.

[0133] S1013. Properly arrange the breeding time of ewes based on local conditions and in a way that is beneficial to the health of the ewes and the development of the lambs.

[0134] For example, the frequent lambing pattern in the pastoral areas of Northwest Sichuan:

[0135] (1). 3 productions in 2 years

[0136] Three births in two years is a method proposed in the late 1950s and is still used today. To achieve three births in two years, lambs are born once every eight months and weaned within two months of age. In this way, lambs are born three times in two years.

[0137] (2) 4 products in 3 years

[0138] Four lambs are born in three years, with a lambing interval of nine months. Lambs are weaned within three months of age. For a ewe that gives birth to one lamb per litter, 1.33 lambs can be obtained in one year.

[0139] (3) Opportunity lambing

[0140] Under favorable conditions, such as favorable feed years and favorable prices, an additional lambing is carried out. No matter what method or system is used for production, try not to have empty ewes. If there are empty ewes, an additional breeding is carried out. This method is a very effective way for individual sheep producers to produce lambs quickly.

[0141] In short, before choosing a specific breeding and lambing model, you should consider factors such as geographical ecology, breed resources, reproductive characteristics, management capabilities, feed resources, equipment conditions, investment needs, and technical level, and make the best choice after careful analysis.

[0142] Step 102. Breeding at the right time

[0143] The selection of the breeding period of Tibetan sheep is mainly based on when the lambing is most conducive to the survival of the lambs and the health of the mother and the child. In the northwest of Sichuan, breeding is carried out in June and July, and lambing is better at the end of the year or the beginning of the next year.

[0144] The breeding time for ewes is that multiparous ewes can be bred in the middle and late estrus, that is, 18-24 hours after the onset of estrus; young ewes can be bred when they are around 7 months old and weigh more than 35kg.

[0145] Step 103. Weaning at the right time

[0146] Lambs are generally weaned at one time, and the weaning time should be considered comprehensively based on the lamb's age, weight, production needs, etc. Tibetan sheep are mainly grazing, and are generally weaned at around 3 months of age.

[0147] S1031. Lamb weaning precautions

[0148] The weight of lambs at weaning has a certain impact on their growth and development after weaning. Considering climate and environmental factors, it is more appropriate to wean Tibetan lambs when they weigh more than 12kg. Feed high-quality forage after weaning: fresh pasture grass or legume hay is best, followed by silage and micro-storage made from crop straw. Supplementary feed is mixed concentrate to ensure the lambs' nutritional needs such as energy, protein, minerals, and vitamins. Provide sufficient clean drinking water.

[0149] S1032. Management during weaning adaptation period

[0150] The weaning adaptation period for lambs is 5-7 days. The main purpose is to allow the lambs to have a certain adaptation process. The feed type cannot be changed suddenly. At the beginning, the same feed type should be provided, and the roughage should be mainly high-quality grass and hay. The proportion of concentrate feed can be gradually increased, and the composition of concentrate feed should also be slowly changed. The energy level of the diet should be gradually increased so that the lambs can adapt to the feeding of high-energy fattening diets. During the adaptation period, feed less frequently to prevent the lambs from eating too much, causing bloating, stopping eating or diarrhea. Generally, feed 3-4 times a day in the first few days, and after 7 days, you can change to free feeding.

[0151] Step 104. Promote estrus after weaning

[0152] S1041. Induce estrus

[0153] Inducing estrus is artificially inducing estrus. It means that during the estrus period of ewes, normal estrus is induced by exogenous factors and breeding is carried out to shorten the breeding cycle of ewes, change seasonal breeding to year-round breeding, implement intensive lambing, achieve 2 litters a year or 3 litters in 2 years, and improve the reproductive capacity of ewes.

[0154] Inducing estrus in sheep can be achieved through early weaning of lambs, hormone treatment and biological stimulation.

[0155] S10411. Early weaning of lambs

[0156] It can eliminate seasonal estrus and make ewes estrus and mate all year round. The specific method is to first wean the lambs early, then treat the ewes with progesterone for about 10 days, and then inject pregnant mare serum gonadotropin after stopping the drug, which can induce estrus and ovulation.

[0157] S10412. Biological stimulation

[0158] Including changes in environmental conditions and sex hormones. Changes in environmental conditions mainly achieve estrus and ovulation by adjusting the light cycle to shorten the daytime. Sex hormones introduce rams into the ewe flock before the normal breeding season, bringing the breeding season forward and shortening the interval from postpartum to ovulation.

[0159] S1042. Synchronous estrus

[0160] The method of estrus synchronization for ewes is called estrus synchronization. It is to use exogenous hormones or other analogs to treat ewes, consciously intervene in their reproductive physiological process, temporarily change the law of their natural estrus cycle, artificially control and adjust the estrus cycle to the same stage, thereby inducing the estrus of the group of ewes in a shorter period of 2-3 days, so as to reasonably organize breeding, make lambing and fattening processes consistent, which is beneficial to the production of meat sheep and the purpose of improving reproduction.

[0161] There are two ways to achieve synchronized estrus: one is to administer progesterone to a group of ewes to be treated at the same time to inhibit the growth and development of ovarian follicles and estrus, and then stop the drug at the same time after a certain period of time, which will cause synchronized estrus. This actually has the effect of prolonging the estrus cycle and delaying the estrus period, creating a baseline for inducing synchronized estrus in the future. Another way is to use another type of hormone with completely different properties to inhibit the corpus luteum, accelerate its regression, shorten the luteal phase, and reduce the level of progesterone, thereby promoting the release of pituitary gonadotropin and causing the estrus period to come earlier. The treatment method is as follows:

[0162] S10421. Vaginal sponge method

[0163] Place a sponge soaked with progesterone at the cervix for 10-14 days, and inject 400-500 international units of pregnant mare serum gonadotropin after stopping the drug. Estrusity will begin after about 30 hours, and insemination will be performed once on the day of estrus and the next day. Common types and doses of progesterone are: progesterone 150-300 mg, medroxyprogesterone 50-70 mg, megestrol acetate 80-150 mg, 18-methyl-norethindrone 30-40 mg, and fluprogesterone 20-40 mg.

[0164] S10422. Oral administration

[0165] Mix a certain amount of the drug evenly into the feed every day and feed it continuously for 12-14 days. The drug dosage is about 1 / 10-1 / 5 of the vaginal sponge method. On the day of the last oral medication, 400-750 international units of pregnant mare serum gonadotropin should be injected intramuscularly.

[0166] S10423. Prostate hormone method

[0167] Infusing a certain dose of prostaglandin F2a (which destroys luteal substances) or its analogues into the uterus or injecting them intramuscularly after the end of estrus can induce estrus in ewes within 2-3 days.

[0168] S1043. Supplemental feeding to stimulate estrus

[0169] Supplementary feeding to induce estrus. One month before mating, improve the diet composition, improve the nutritional level of the ewes, and especially supplement protein feed. Supplementary feeding can not only increase the estrus rate of ewes, but also increase the number of ovulations, inducing ewes to give birth to twins or even multiple births.

[0170] Step 2. Improve the nutritional level of ewes

[0171] Step 201. When the energy level is appropriate, the sheep will begin to estrus when their weight reaches about 35%-70% (6-8 months old) and 60% (5-10 months old) of their adult weight. When the energy level is insufficient, the growth is slow and the initial stage is delayed; when the energy level is high, the first estrus is advanced.

[0172] Step 202. Relationship between energy and ovulation and lambing rate

[0173] Practice has shown that it is best to keep the ewe's body condition at an above-average level during breeding. For extremely thin ewes, improving the feeding nutrition level before breeding, increasing the feed intake, supplementing the feed with compound feed, and adding alfalfa hay can improve the body condition and increase the ewe's ovulation rate.

[0174] Step 203. Short-term feeding to improve nutrition

[0175] Experiments have shown that the reproductive capacity of ewes is closely related to their weight. The heavier the weight of sheep of the same breed at the time of mating, the higher their reproductive capacity. The weight is determined by the nutritional level. It is estimated that for every 4.5kg increase in the weight of Merino before mating, the number of twin lambs can increase by 3%-5%. In Egypt, some people found that when the weight of ewes is lower than 40.9-45.5kg at the time of mating, the infertility rate will increase. According to data analysis, for every 1kg increase in the weight of sheep at the time of mating, the birth rate will increase by 2.1%.

[0176] Step 204. Sheep mineral supplementation

[0177] S2041. Calcium and phosphorus

[0178] When there is a lack of calcium in the diet, it causes postpartum paralysis in high-yielding Small Tail Han sheep. This is because Small Tail Han sheep give birth to many lambs, and the amount of calcium lost with breast milk exceeds the amount absorbed and the amount of supplementary calcium mobilized from the bones. In addition, the speed of calcium mobilization is reduced, and the ability of the intestine to absorb calcium is reduced, resulting in severe calcium deficiency and postpartum paralysis. In addition, the improper calcium-phosphorus ratio is also one of the reasons.

[0179] S2042. Selenium

[0180] It is reported that in a selenium-deficient pasture, ewes were injected with 6 mg of selenium and 272 I U of vitamin E 4 weeks before mating, resulting in an increase in the average number of lambs born per ewe from 1.03 to 1.22.

[0181] S2043. Zinc

[0182] In the diet of breeding rams, 0.5-1.0 mg of zinc sulfate per kilogram of body weight is added, and the semen quality of the rams is the best, and the estrus conception rate of the ewes is the highest. Zinc deficiency can cause all sexual organs to become smaller, testicular growth and development to be hindered, sexual maturity to be delayed, testicular reproductive epithelium to atrophy, and zinc content in the testicles, epididymis and prostate to decrease.

[0183] S2044. Magnesium

[0184] Ewes fed a low magnesium diet (less than 8 mg / kg) required more services per conception than ewes fed a magnesium-supplemented diet (2.5 vs. 1.5, respectively). Magnesium deficiency in ewes can cause conception failure and embryonic death.

[0185] S2045. Iodine

[0186] Iodine deficiency causes infertility in both cattle and sheep. In areas where goiter is common in lambs, supplementing 0.3 mg / kg of iodized salt can solve the problem of infertility in ewes.

[0187] S2046. Vitamin A

[0188] Lack of vitamin A in the feed will lead to anestrus, abnormal estrus, stillbirth or fetal malformations, such as blindness, retained placenta, etc., and will cause inflammation of the reproductive organs in ewes, corpus luteum and follicular cysts, reduced conception rate, obstructed placental formation, and embryonic death.

[0189] S2047. Vitamin E deficiency

[0190] Lack of vitamin E can lead to decreased ovarian function, abnormal sexual cycle, infertility, abnormal embryonic development or stillbirth. Supplementing vitamin E to ewes can reduce the incidence of reproductive diseases such as retained placenta, mastitis and ovarian cysts. When rams lack vitamin E, their testicles degenerate, atrophy, sperm motility is abnormal and they can even fail to produce sperm.

[0191] Step 3. Nutritional regulation of ewes

[0192] According to the physiological stage of ewes, there are three stages: empty period, pregnancy period and lactation period. Breeding ewes are the basis for expanding the flock. The main task of breeding ewes is to promote normal estrus, ovulation, lactation and improve the reproduction rate. Therefore, ewes at each stage should be fed reasonably according to different production links such as breeding, pregnancy and lactation, so that the ewes can estrus, breed and reproduce normally.

[0193] S301. Nutritional regulation of empty-pregnant ewes

[0194] After weaning, lactating ewes have poor physical condition, so it is necessary to strengthen feeding management and give them adequate grazing to quickly restore their physical condition and promote normal estrus, ovulation and conception. Before mating, empty-stomach ewes can be fed with short-term good feeding: 10-15 days before mating, the ewes are supplemented with 0.2 kg of concentrated feed per day, and appropriate carrots or vitamins, which is convenient for estrus and ovulation of ewes and implantation of fertilized eggs, so that they can produce more lambs in a concentrated manner.

[0195] S302. Nutritional regulation of pregnant ewes

[0196] The gestation period of sheep is about 150 days, which can be divided into the early pregnancy and late pregnancy. The early pregnancy is 3 months after conception. The fetus develops slowly and has the same nutritional needs as the empty period. Grazing can meet the needs. The late pregnancy is the last 2 months of pregnancy. The fetus grows rapidly and the weight gain accounts for about 80% of the birth weight. This stage requires full nutrition. The late pregnancy is the dry grass period. Insufficient nutrition will cause the weight of the ewe to drop, which will affect the development of the fetus. The lambs are born with small weight, imperfect body temperature regulation function, weak resistance, and easy to die. It has a great impact on meat sheep, which is related to the development of the fetus and the increase in the growth rate of the lambs after birth. Therefore, sufficient nutrients are needed at this stage, and the heat metabolism level should be increased to 15%-20%. The need for phosphorus and calcium should be increased by 40%-50%, and the calcium-phosphorus ratio should be 2 to 1. Sufficient vitamin A and vitamin D are indispensable in the late pregnancy.

[0197] S3021. Early pregnancy (about 3 months after mating)

[0198] The energy and protein requirements are slightly higher than those of the empty period, so a certain amount of high-quality feed with high protein content should be supplemented. The ewes are required to maintain a medium or above fat condition.

[0199] (1) About one month of pregnancy is a critical period to ensure the normal growth and development of the fetus. At this time, the fetus is still small, and the nutrients required by the ewe are not high, but must be relatively comprehensive. Especially in late autumn, winter and early spring, the grass in the pasture is withered and coarse. Due to the limitations of nutrients in the forage, farmers should appropriately supplement the concentrated feed according to the nutritional status of the ewe.

[0200] (2) After 2 months of pregnancy, as the pregnancy progresses, the fetus develops faster and the amount of supplementary concentrate feed should be gradually increased. Pregnant sheep can be fed 2-3 times a day, with each sheep being fed 50-100 grams of mixed concentrate each time. The amount of concentrate feed for young ewes should also be appropriately increased.

[0201] (3) After three months of pregnancy, the total volume of forage fed to pregnant sheep should be properly controlled, and supplementary feeding should be done in small amounts and frequently to prevent excessive feeding at one time from compressing the fetus and affecting normal growth and development.

[0202] S3022. Late pregnancy (about 2 months before delivery)

[0203] This is a period of rapid fetal growth. More than 80% of the fetus's body weight is generated during this period. Adequate nutrients need to be supplied. The dry matter requirement should be increased by 30%-40%, protein by 40%-60%, calcium and phosphorus by 1.2 times, and vitamins A and D should be supplemented. At the same time, high-quality hay and mixed feed with high nutritional value should be supplemented. During this period, the energy content should not be too high. In addition to grass feed, about 0.4 kg of concentrated feed should be supplemented every day. In the late pregnancy, the focus is on protecting the fetus and preventing miscarriage.

[0204] (1) After 4 months of pregnancy, the weight of the fetus has reached 60-70% of the lamb's birth weight. At the same time, the ewe needs to store a certain amount of nutrients for postpartum lactation. Generally, during this stage, the fetus is supplemented with feed. The amount of concentrated feed should be increased to about twice that of the early pregnancy. The forage and supplementary concentrated feed should be fresh and diversified. Young, green and juicy feed can be fed more. It is forbidden to feed cottonseed cake or rapeseed cake, potatoes, and distiller's grains that have not been detoxified. It is forbidden to feed moldy, spoiled, overcold or overheated, acidic, or mixed with ergot or poisonous grass, so as to avoid causing abortion, dystocia, and postpartum diseases in the ewe.

[0205] (2) About one month before delivery, control the amount of roughage fed and feed soft feed as much as possible to facilitate bowel movements.

[0206] (3) About 10 days before delivery, reduce the amount of feed according to the ewe's appetite and digestive conditions.

[0207] (4) 2-3 days before delivery, for ewes with good physical condition, reduce the amount of feed in the original diet by 1 / 3-1 / 2 to prevent excessive milk or too thick milk in the early stage of delivery, which may cause mastitis, milk regurgitation and diarrhea in the lambs due to indigestion. For relatively thin ewes, whose udders are shriveled within 1 week before delivery, in addition to reducing the amount of roughage, they should also appropriately increase the amount of protein-rich lactation feed such as soybean cake and soybean dregs, as well as green and juicy laxative feed to prevent the ewe from lacking milk after delivery.

[0208] S3023. Nutritional regulation of lactating ewes

[0209] The main task of this stage is to provide lambs with sufficient milk. Feeding and management must be carried out according to the lactation law of ewes and the physiological conditions after delivery. In the first few days after delivery, care must be strengthened. Feeding is mainly barn feeding, with high-quality tender grass and hay as the main feed. Clean drinking water is given 3-4 times a day, and a small amount of salt and bran are added to the drinking water, or rice soup is fed to allow it to drink freely. If the ewe has sufficient milk, no or less concentrate feed can be supplemented. When lactation is insufficient, the ewe can be supplemented with green and juicy feed and an appropriate amount of concentrate feed. 15-20 days after delivery, supplementary feeding can be appropriately increased according to the amount of milk of the ewe. Generally, 0.3-0.5 kg of concentrate feed can be supplemented every day, and high-quality green feed should be fed as much as possible to stimulate the full play of lactation function. In management, attention should be paid to keeping the shed dry and clean, and regular feces cleaning and disinfection should be done; do not graze in bushes and thorns to avoid stabbing the breasts.

[0210] S303. Precautions for breeding and management of breeding ewes:

[0211] (1) Carry out daily feeding and management according to feeding standards and breeding plans.

[0212] (2) During the non-breeding period, breeding ewes and reserve breeding ewes should be grouped and managed.

[0213] (3) Feeding and management of breeding ewes during the empty period. After weaning, the ewes are in a weak body condition and should be fed with green and roughage ad libitum. Each ewes should be fed with about 0.3 kg of concentrated feed per day to gain weight and regain strength.

[0214] (4) Feeding and management during pregnancy. The ewes’ demand for nutrients increases significantly during pregnancy (especially in the late pregnancy). Feeding and management should be strengthened, and complete concentrates (0.6-0.8kg / day per sheep) should be supplemented. If it is the dry grass season, a certain amount of silage should be supplemented to ensure their nutritional needs.

[0215] (5) In the late pregnancy, ewes should maintain a certain amount of exercise, about 4 hours a day. Try to avoid re-grouping in the late stage to avoid fighting and miscarriage.

[0216] (6) Feeding and management during the lactation period: In order to increase the milk production of ewes in the early stage of lactation, increase the supplementary feeding of concentrated feed and green fodder to ensure their nutritional needs. Supplementary feeding can be used as appropriate in the later stage of lactation.

[0217] (7) Keep the pens clean and conduct regular medicated baths, deworming and vaccinations.

[0218] (8) Regularly perform hoof trimming and other management.

[0219] S304. Recommended formula for supplementary feed for ewes

[0220] Table 1 Recommended formula for supplementary feed for ewes

[0221]

[0222] Step 4. Disease prevention and control

[0223] S401. Strict disinfection

[0224] The disinfection room is an important measure to implement the principle of "prevention first". Its purpose is to eliminate the source of infection, cut off the transmission route, and prevent the disease from spreading further. A practical disinfection system can be established to regularly disinfect the sheep house (including utensils), ground soil, feces, sewage, fur, etc.

[0225] Table 2 Commonly used disinfectants and their use

[0226]

[0227] S402. Regular deworming

[0228] Regular deworming is an important measure to treat and prevent various parasitic diseases. It can also prevent sheep from further developing serious damage after being mildly infected with parasites. According to the situation of the sheep, deworming can be arranged once in April and October each year. Preventive deworming is beneficial for sheep to gain weight and safely survive the winter and spring shortage period.

[0229] The drugs you can choose are:

[0230] (1) To expel nematodes in the body: levamisole, albendazole, ivermectin, etc.

[0231] (2) Anti-tapeworms: closacil, praziquantel, dichlorophen sulfate or methotrexate (niclosamide), etc.

[0232] (3) To eliminate external parasites: injection of ivermectin or avermectin or bathing in 0.5-1% dichlorvos aqueous solution, etc.

[0233] S403.Immunity

[0234] Table 3. Immunization schedule

[0235]

[0236] Immunization considerations:

[0237] (1) The interval between each vaccine injection and deworming is 7-10 days.

[0238] (2) It is best not to immunize against diseases that have not occurred locally, such as sheep pox, peste des petits ruminants, etc.

[0239] Example

[0240] In the alpine pastoral area of ​​northwest Sichuan, 60 healthy Tibetan sheep ewes with 2-6 parities were selected and divided into two groups, A and B, with 30 sheep in each group for the experiment. Group A was managed according to the method of the present invention, and the lambs were weaned at 3 months of age; Group B was used as the control group, which was raised in a full grazing manner and the lambs were weaned naturally. The production cycles of the two groups were compared. The management method was implemented according to the present invention. The results showed that the average production cycle of the ewes in group A was 262.5 days, 4.17 lambs were born in 3 years, 1.39 lambs were born per year, and the lambing lasted 38 days; the average production cycle of the ewes in group B was 367.2 days, 2.98 lambs were born in 3 years, 1 lamb was born per year, and the lambing lasted 62 days.

[0241] After nutritional regulation, the average production cycle of ewes is shortened by 104.7 days compared with ewes in a fully grazing state, and the average annual lambing is 1.39. Since Tibetan sheep are single lambs, each ewe can produce 0.39 more lambs per year, that is, the lambing rate is 139%, which is 39% higher than that of fully grazing ewes. The results show that after the management method of the present invention, the lambing period of the group of ewes is significantly shortened compared with the ewes in a fully grazing state, that is, the lambing time of the group is more concentrated, which improves the reproduction rate of the ewes and is more conducive to feeding and management.

[0242] Finally, 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 aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for improving the reproduction rate of Tibetan sheep through management methods, characterized in that: The following steps are involved: Step 1. Improve the efficient reproduction rate of ewes Step 100. Select the male and female parent The rams are selected from White Suffolk sheep and Hu sheep with strong body, obvious breed characteristics, well-developed testicles, strong virility and good semen quality; the ewes are selected from Tibetan sheep with large body, good maternal instinct, good lactation and breastfeeding performance; Step 101. Increase the proportion of breeding ewes of suitable age and implement frequent lambing Increase the proportion of ewes in the flock, the proportion of ewes in the flock is increased to 70%, the proportion of ewes of appropriate age reaches more than 50%, and lambing is achieved frequently; Step 102. Breeding at the right time In the northwest of Sichuan, ewes are bred in June and July, and multiparous ewes are bred 18-24 hours after the onset of estrus. Step 103. Weaning at the right time The lambs are weaned at one time and fed with high-quality forage after weaning. The lambs have a weaning adaptation period of 5-7 days and are still provided with the same feed type. Step 104. Promote estrus after weaning S1041. Induce estrus Inducing estrus is achieved through early weaning of lambs, hormone treatment, and biological stimulation; S1042. Synchronous estrus One is to administer progestogen to a group of ewes to be treated at the same time to inhibit the growth and development of ovarian follicles and estrus, and then stop the administration at the same time after a certain period of time, which will then cause simultaneous estrus; another way is to use another type of hormone with completely different properties to inhibit the corpus luteum, accelerate its regression, shorten the luteal phase, and reduce the progesterone level; S1043. Supplemental feeding to stimulate estrus Improve the diet composition one month before breeding; Step 2. Improve the nutritional level of ewes Mineral supplementation for sheep: calcium and phosphorus are added to the diet, 6 mg of selenium and 272 I U of vitamin E are injected into ewes 4 weeks before mating, 0.5-1.0 mg of zinc sulfate per kilogram of body weight is added to the diet of breeding rams, magnesium-supplemented diets are fed, vitamin A is supplemented in the diet by supplementing iodized salt containing 0.3 mg / kg, and vitamin E is supplemented for both ewes and rams; Step 3. Nutritional regulation of ewes According to the physiological stage of ewes, there are three stages: empty period, pregnancy period and lactation period. Before mating, the empty period ewes should be fed with short-term good feeding: 10-15 days before mating, the ewes should be fed with 0.2 kg of concentrate daily, and appropriate carrots or vitamins; in the early stage of pregnancy, they should be raised by grazing, and in the late stage of pregnancy, the phosphorus and calcium needs should be increased by 40%-50%, and the calcium-phosphorus ratio should be 2:1, with sufficient vitamin A and vitamin D; First trimester Feed concentrates for about one month of pregnancy. After two months of pregnancy, gradually increase the amount of concentrates. Feed pregnant sheep 2-3 times a day, 50-100 grams of mixed concentrates for each sheep each time. Increase the amount of concentrates for young ewes appropriately. After three months of pregnancy, feed less and more frequently. Late pregnancy After 4 months of pregnancy, the amount of concentrated feed increased to about two times that of the early pregnancy, and the forage and supplementary concentrated feed should be fresh and diversified, and young green and juicy feed should be fed more. One month before delivery, control the amount of roughage and feed soft feed. Ten days before delivery, reduce the amount of feed according to the appetite and digestion of the ewe. 2-3 days before delivery, for ewes with good physique, reduce the amount of feed from the original diet by 1 / 3-1 / 2; for relatively thin ewes, in addition to reducing the amount of roughage, appropriately increase the protein-rich lactation feed of bean cake and bean dregs, as well as green and juicy mild laxative feed; Nutritional Regulation of Lactating Ewes The main method of feeding is to feed in a shed, with high-quality tender grass and hay as the main feed. Clean drinking water is provided 3-4 times a day, and a small amount of salt and bran is added to the drinking water, or rice soup is fed to the ewes for free drinking. When the lactation is insufficient, the ewes are supplemented with green and juicy feed and an appropriate amount of concentrated feed. 15-20 days after the ewes give birth, the supplementary feeding is appropriately increased according to the amount of milk of the ewes, and 0.3-0.5 kg of concentrated feed is supplemented every day, and high-quality green feed is fed. In terms of management, attention should be paid to keeping the sheds dry and clean, and regular feces cleaning and disinfection are carried out. Formula for supplementary feed for ewes: Each 1kg of feed is made of the following raw materials in the following weight ratio: 50% corn, 12% wheat, 12% soybean meal, 15% rapeseed meal, 3% salt, 3% baking soda, and 5% sheep premix; Pregnancy In the early stage of pregnancy, the supplementary feeding is 0.3kg / d; in the late stage of pregnancy, the supplementary feeding is 0.6kg / d; No supplementary feeding 1-2 days before lambing; Lactation No supplementary feeding is done on the day of lambing. Depending on the body condition of the ewe and the number of lambs, supplementary feeding is increased from less to more within one week, up to 0.5-0.8 kg / d per lamb; the amount is gradually reduced to 0.3 kg / d one week before weaning, and no supplementary feeding is done 1-2 days before weaning. Empty period No supplementary feeding is done on the first 1-2 days after weaning to encourage the ewes to recover milk as soon as possible; then gradually supplementary feeding to 0.3kg / d over the next 3 days, and on the 10th day after weaning, supplementary feeding begins at 0.5kg / d to promote estrus of the ewes; Step 4. Disease prevention and control S401. Strict disinfection Disinfection method: Spray 10%-20% lime milk on the ground, drainage ditches, feces, and soil; spray 5% or 10%-20% bleaching powder solution on sheep pens, sports fields, ditches, and feces. 5% solution kills common pathogens, and 10%-20% solution kills spores; spray compound phenol on livestock and poultry pens, utensils, and field excrement. The ratio of disinfectant solution to water is 1:

300. When foot-and-mouth disease occurs, the ratio of solution to water is 1:

200. Spray 0.5%-1.0% strong disinfectant on pens, fields, and drainage ditches. Spray 1%-2% sodium hydroxide on livestock pens, ground, and utensils. It has a strong killing effect on livestock pens, ground, and utensils contaminated with bacteria or viruses. S402. Regular deworming Arrange deworming once in April and October each year; S403.Immunity The immunization treatment steps are as follows: 20-30 days before the pregnant ewe gives birth, the ewe is subcutaneously injected with 2ml of lamb dysentery vaccine, and 3ml is injected again after 10 days. The ewes are immune for 5 months, and the lambs are passively immunized by eating milk to prevent lamb dysentery. In March-April and September-October each year, one month after the ewe gives birth and one month after the lamb is born, the ewe is intramuscularly injected with 2ml / lamb and the lamb is injected with 1ml / foot-and-mouth disease AO-Asia type I triple vaccine to prevent foot-and-mouth disease. 6 months of immunity is generated 15 days after the injection. Once in spring and autumn each year, the sheep triple-defense quadruple vaccine is injected intramuscularly according to the instructions for use to prevent sheep rapid disease, sheep enterotoxemia, sheep anthrax, and sheep black disease. 6 months of immunity is generated 10-14 days after the injection. In February-March each year, 0.5ml of sheeppox chicken embryo attenuated vaccine is injected intradermally to prevent sheeppox disease, and the immunity period is maintained for 1 year 6-10 days after the injection.

2. The method according to claim 1, characterized in that Inducing estrus includes: (1) Early weaning of lambs First, wean the lambs early, then treat the ewes with progesterone for 10 days, and then inject pregnant mare serum gonadotropin after stopping the drug; (2) Biological stimulation It includes changes in environmental conditions and sex hormones. Changes in environmental conditions shorten the daylight period by adjusting the light cycle, and sex hormones advance the breeding season and shorten the interval from postpartum to ovulation by introducing rams into the ewe flock before the normal breeding season begins.

3. The method according to claim 1, characterized in that Treatment methods for estrus synchronization include: (1) Vaginal sponge method Place a sponge soaked with progesterone at the opening of the cervix for 10-14 days. After stopping the drug, inject 400-500 international units of pregnant mare serum gonadotropin. Estrus will begin after 30 hours. Insemination will be performed once on the day of estrus and the next day. The types and dosages of commonly used progesterone are: progesterone 150-300 mg, medroxyprogesterone acetate 50-70 mg, megestrol acetate 80-150 mg, 18-methyl-norethindrone 30-40 mg, and fluprogesterone acetate 20-40 mg. (2) Oral administration Evenly mix a certain amount of the drug into the feed every day and feed it continuously for 12-14 days. The drug dosage is 1 / 10-1 / 5 of the vaginal sponge method. On the day of the last oral medication, 400-750 international units of pregnant mare serum gonadotropin should be injected intramuscularly. (3) Prostate hormone method After the end of estrus, a certain dose of prostaglandin F2a or its analogues is infused into the uterus or injected intramuscularly to induce estrus in the ewe within 2-3 days.

4. The method according to claim 1, characterized in that Frequent lambing requirements: (1) Select healthy, strong and well-nourished ewes, aged 2-6 years old; (2) The ewes must have good supplementary feeding conditions before and after calving; (3) Properly arrange the breeding time of ewes.

5. The method according to claim 1, characterized in that Step three also includes breeding ewe feeding management: (1) Carry out daily feeding and management according to feeding standards and breeding plans; (2) During the non-breeding period, breeding ewes and reserve breeding ewes are grouped and managed; (3) Feeding and management of breeding ewes during the empty period. After weaning, the ewes are weak and thin. They are fed with green and roughage ad libitum. Each ewe is supplemented with about 0.3 kg of concentrated feed per day to gain weight and regain strength. (4) Feeding and management during pregnancy. The demand for nutrients during pregnancy increases significantly. Feeding and management should be strengthened, and complete concentrates should be fed. If it is the dry grass season, a certain amount of silage should be fed. (5) In the late pregnancy, ewes should maintain a certain amount of exercise, 4 hours a day, and avoid re-grouping in the late stage; (6) Feeding management during lactation period, strengthen supplementary feeding of concentrated feed and green feed in the early stage of lactation; (7) Keep the pens clean and perform regular bathing, deworming and vaccination; (8) Carry out regular hoof trimming.

6. The method according to claim 1, characterized in that Regular deworming medications include: (1) Expelling nematodes from the body: levamisole, albendazole, ivermectin; (2) To remove tapeworms: closacil, praziquantel, dichlorophen sulfate or methotrexate; (3) To eliminate external parasites: injection of ivermectin or avermectin or bathing in 0.5-1% dichlorvos aqueous solution.

7. The method according to claim 1, characterized in that the immunization Require: (1) The interval between each vaccine injection and deworming is 7-10 days; (2) No immunization will be conducted for diseases that have not occurred locally.

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