CN113331132B

CN113331132B - Treatment method for improving summer reproduction rate and milk yield of dairy cows by adopting capsaicin

Info

Publication number: CN113331132B
Application number: CN202110593883.1A
Authority: CN
Inventors: 杨利国; 滑国华; 安志高; 阿地力·阿不来提
Original assignee: Huazhong Agricultural University
Current assignee: Huazhong Agricultural University
Priority date: 2021-05-28
Filing date: 2021-05-28
Publication date: 2022-06-21
Anticipated expiration: 2041-05-28
Also published as: CN113331132A

Abstract

The invention provides a treatment method for improving the summer reproduction rate and the milk yield of dairy cows by adopting capsaicin, which comprises the following steps: s1, selecting the 20 th day of postpartum cow, adding capsaicin into the daily ration, and continuously feeding for one month; s2, on the 50 th day after the dairy cow parturition, recording as the 0 th day of the synchronous estrus treatment of the dairy cow, and injecting gonadotropin releasing hormone into the healthy dairy cow in the estrus cycle; s3, day 7, intramuscular injection of PGF2 a; s4, on the 9 th day, injecting gonadotropin releasing hormone for the second time, and simultaneously injecting mifepristone to promote ovulation; s5, on the 10 th day, artificial insemination is performed; s6, injecting human chorionic gonadotropin intramuscularly at day 15, namely day 5 after artificial insemination. The invention can effectively improve the estrus rate, the mating rate and the conception rate of the postpartum dairy cows in the same period, improve the milk yield of the dairy cows and improve the milk components; and need not detect estrus, regularly insemination convenient operation.

Description

Treatment method for improving summer reproduction rate and milk yield of dairy cows by adopting capsaicin

Technical Field

The invention belongs to the technical field of dairy cow breeding in animal husbandry, and particularly relates to a treatment method for improving the summer breeding rate and milk yield of dairy cows by adopting capsaicin.

Background

Although a cow is an estrus livestock throughout the year, the reproductive performance of the cow is easily affected by factors such as environment and climate. In summer, heat stress can cause the decrease of the feed intake of the dairy cows, the decrease of appetite, imbalance of energy supply and demand and influence on reproductive performance. The cow, especially the high-yield cow, is easy to cause the increase of the incidence rate of reproductive disorders such as abnormal estrus, quiet estrus, delayed ovulation, reproductive tract inflammation and the like during the postpartum lactation peak period, and can cause the increase of the early embryonic mortality rate and the increase of the proportion of frequently-bred infertile cows, thereby influencing the economic benefit of a pasture.

The estrus-timing insemination technology is widely applied to the production of dairy cows, the ovarian activity is artificially regulated and controlled and the estrus cycle and ovulation time are controlled through different combinations of reproductive hormones, the estrus identification is not needed, the operation is simple, and the conception rate of the dairy cows can be obviously improved. The Ovsynch-TAI estrus synchronization scheme is widely applied to livestock breeding, but the estrus synchronization effect in summer is not ideal, which is shown in that the conception rate in the estrus in summer is obviously reduced, the early mortality rate of embryos is increased, and the main reason is that heat stress causes blood circulation on the body surface, so that the blood supply of digestive, reproductive and lactation systems is insufficient, digestion, reproduction and lactation are influenced, the milk yield is greatly reduced, and the technical problem to be solved is how to effectively improve the summer reproductive rate of cows and the yield and quality of cows is urgent.

Disclosure of Invention

In order to solve the technical problems, the invention provides a treatment method for improving the summer reproduction rate and the milk yield of the dairy cows by adopting capsaicin, and simultaneously, the method can greatly improve the milk yield.

In order to achieve the purpose, the invention adopts the following technical scheme that:

a treatment method for improving the summer reproductive rate and milk yield of dairy cows by adopting capsaicin comprises the following steps:

s1, selecting the 20 th day of postpartum cow, adding capsaicin into each kilogram of daily ration, and continuously feeding for one month (30 days), wherein the day of parturition is recorded as 0 day;

s2, on the 50 th day after delivery, marking as the 0 th day of the cow synchronous estrus treatment, injecting gonadotropin releasing hormone (GnRH) into the healthy cow muscle in the estrus cycle to induce estrus;

s3, day 7, intramuscular injection of treprostinil sodium (PGF2 a) to initiate estrus;

s4, day 9, injecting gonadotropin releasing hormone (GnRH) for the second time, and simultaneously injecting mifepristone to promote ovulation;

s5, on the 10 th day, 16 hours after the mifepristone is injected, carrying out artificial insemination;

s6, at day 15, i.e. at day 5 after artificial insemination, intramuscular injection of human chorionic gonadotropin (hCG) to promote early embryo survival;

and S7, determining the pregnancy condition of the cattle by B ultrasonic on the 50 th day, namely the 40 th day after artificial insemination.

In the method, in step S1, the daily supplementary feeding amount of capsaicin is preferably 1-4 mg/kg Total Mixed Ration (TMR) daily ration.

The method as described above, preferably, the injection dose of gonadotropin releasing hormone (GnRH) is 200 μ g/head in steps S2 and S4.

The method as described above, preferably, the injection of the treprostinil sodium in step S3 is injected on day 7 after step S2. Further, the injection dosage of the PGF2 alpha is 0.5 mg/head.

The method as described above, preferably, in step S4, the second injection of gonadotropin releasing hormone GnRH is separated from the first injection by 9 days.

The method as described above, preferably, in step S4, the injectable dose of mifepristone is 0.4mg/kg body weight.

In the method as described above, preferably, in step S6, the hCG is injected in a dose of 2000 IU/head.

The application of capsaicin in increasing the conception rate of the cow in summer and increasing the milk yield.

The application is that 1-4mg of the capsaicin is added into TMR per kg of the cow on the 20 th day (day 0 of delivery) before the estrus treatment in the same period, and the cow is continuously fed for one month (30 days); on the 50 th day after delivery, namely the 0 th day of the same estrus treatment of the cows, the gonadotropin releasing hormone GnRH is injected intramuscularly in the afternoon, the cloprostenol sodium PGF2 alpha is injected intramuscularly in the afternoon on the 7 th day, the gonadotropin releasing hormone GnRH is injected intramuscularly in the afternoon on the 9 th day, mifepristone is injected at the same time, the artificial insemination is carried out in the afternoon on the 10 th day (16 hours after the mifepristone is injected), hCG is injected intramuscularly in the cattle to be bred on the 15 th day (namely the 5 th day after the artificial insemination), and the pregnancy condition of the cattle is determined by B ultrasonic on the 50 th day (namely the 40 th day after the artificial insemination).

Preferably, the capsaicin is added into one kilogram of TMR and is continuously fed for 30 days, wherein the amount of the capsaicin is 1-4 mg; the injection dosage of the gonadotropin releasing hormone GnRH is 200 mu g/head; the injection dosage of the PGF2 alpha is 0.5 mg/head; the injection dosage of the mifepristone is 0.4mg/kg body weight; the injection dosage of the human chorionic gonadotropin hCG is 2000 IU/head.

In the research process, the invention discovers that the effect of low capsaicin supplementary feed amount is not obvious, the feeding cost is increased and the feed intake of the dairy cow is reduced, and the effect of high capsaicin supplementary feed amount is not stronger than that of 1-4 mg/kg daily ration and is not very good, so that the optimal dosage of capsaicin is 1-4 mg/kg daily ration, and the optimal dosage is 4mg/kg daily ration.

The dosage of gonadotropin releasing hormone (GnRH) on the dairy cattle is 50-250 mu g/head generally, but the optimal dosage of the gonadotropin releasing hormone (GnRH) injected into the dairy cattle is 200 mu g/head in the research process, the ovulation rate is influenced by too low dosage, the economic investment is increased by too high dosage, and the ovulation of multiple follicles is easily caused by too high dosage. Human chorionic gonadotropin (hCG) is injected intramuscularly, the optimal injection dose is 2000 IU/head, and the low dose or the high dose is not good for the survival of early embryo. The PGF2 alpha intramuscular injection dosage of the invention is 0.5 mg/head, and if the dosage is too low, incomplete luteolysis can be caused, and the synchronous estrus rate is influenced.

The invention has the beneficial effects that:

the processing method for improving the summer reproductive rate and milk yield of the dairy cows by adopting the capsaicin organically combines the capsaicin and GPGMH synchronous estrus method, promotes the blood circulation of a digestive system, a reproductive system and a lactation system, increases energy intake, relieves energy negative balance, further promotes follicular development and ovulation, not only can improve the synchronous estrus rate, mating rate and conception rate of the dairy cows in summer, but also can obviously improve the milk yield of the dairy cows, improve milk components, and obviously improve total solid matters, lactose content, protein content and butter fat rate, further saves the breeding cost and improves the breeding benefit.

The invention provides a new application of capsaicin, and the capsaicin can promote blood circulation if added into feed, improve digestion and relieve energy negative balance by promoting the blood circulation of digestive tract, reproductive tract and lactation system, further promote follicular development and ovulation, promote lactation and the like, and broaden the utilization rate of capsaicin.

Drawings

FIG. 1 is a flow chart of the method of the present invention for simultaneous estrus and timing insemination using capsaicin + GPGMH.

Fig. 2 shows the follicular development law of daily ration of Holstein cows with different dosages of capsaicin.

FIG. 3 is a graph of the effect of different doses of capsaicin on milk production performance.

Detailed Description

The following examples are intended to further illustrate the invention but should not be construed as limiting it. Modifications and substitutions may be made thereto without departing from the spirit and scope of the invention.

The experimental results of the present invention were obtained in summer, and the technical means used in the examples are conventional means well known to those skilled in the art, unless otherwise specified.

Example 1

In the test, 1-4mg of capsaicin is added into each kilogram of TMR of the postpartum dairy cow to research the influence of the capsaicin on the follicular development, the oestrus rate, the conception rate, the lactation rate and the blood biochemical indexes of the dairy cow so as to improve the conception rate of the dairy cow in summer and improve the milk yield of the dairy cow. 101 healthy perinatal cows with good body conditions are selected, cows on the 20 th day after delivery (day of delivery is recorded as 0 day) are selected, divided into 4 groups (the indexes of weight, age, fetal number, milk yield and the like are evenly distributed in each group), and fed with daily ration prepared by adding 0, 2, 4 and 6mg of capsaicin to each kilogram of TMR for one month (30 days). In the test I group, 2mg of capsaicin is added into each kilogram of TMR from 20 days after delivery, and supplementary feeding is continuously carried out for 30 days from 20 days after delivery to 50 days after delivery; in group II, 4mg of capsaicin is added into each kilogram of TMR from 20 days after delivery, and supplementary feeding is continuously carried out for 30 days from 20 days after delivery to 50 days after delivery; group III, starting 20 days after delivery, adding 6mg of capsaicin into each kilogram of TMR, and continuously feeding for 30 days from 20 days after delivery to 50 days after delivery; the control group did not add capsaicin. On the 50 th day after delivery, the 0 th day of the cow synchronous oestrus treatment is counted, GnRH is injected intramuscularly in the afternoon, cloprostenol sodium PGF2 alpha is injected intramuscularly in the afternoon on the 7 th day, GnRH is injected intramuscularly in the afternoon on the 9 th day, mifepristone is injected simultaneously, artificial insemination is performed in the afternoon on the 10 th day (16 hours after the mifepristone is injected), hCG is injected intramuscularly in a cow to be bred on the 15 th day (5 days after the artificial insemination), pregnancy of the cow is determined by B ultrasonic on the 50 th day (40 days after the artificial insemination, and dry matter feed intake, milk yield, milk components, serum biochemical indexes, oxidation resistance indexes, oestrus rate, ovulation rate and conception rate of the cow are respectively measured. The method comprises the following specific steps:

cows at 20 days after delivery (day of delivery is recorded as 0 day) are selected, divided into 4 groups (the indexes of weight, age, fetal number, milk yield and the like are evenly distributed in each group), and fed with daily ration containing 0, 2, 4 and 6mg of capsaicin per kg of TMR for one month (30 days). On the 50 th day after delivery, the cow is counted as the 0 th day of the contemporaneous estrus treatment, GnRH is injected intramuscularly in the afternoon (200 mu g/head), B ultrasonic examination is carried out from the 6 th day (one day before PGF2 alpha injection) to the 12 th day of ovulation (namely 72h after the second GnRH injection), and follicular development, estrus and ovulation conditions are recorded; the results are shown in Table 1, where the animals were injected intramuscularly at PGF2 a on day 7 afternoon, at 0.5 mg/head, with GnRH (200. mu.g/head) a second intramuscular injection at day 9 afternoon (48 hours after PGF2 a injection), with mifepristone injection, with artificial insemination at day 10 afternoon (16 hours after mifepristone injection), and with hCG injected intramuscularly at day 15 (i.e. day 5 after artificial insemination) into the cattle to be bred. Considering the problem of early embryonic death, pregnancy diagnosis was performed 40 days after artificial insemination, and the whole flow chart is shown in fig. 1.

1.1 Effect of supplementary feeding of different doses of capsaicin on cow follicular development

The experimental results from table 1 show that with different doses of capsaicin added to the daily ration of hestan cows, the maximum follicle diameter (13.8 ± 0.4mm) in the medium dose group (4mg/kg) is significantly (p <0.05) greater than that in the blank group (0 capsaicin is 0 group, 11.5 ± 1.5mm), but there is no significant difference in the other dose groups. The interval between the second GnRH injection and the ovulation, the interval between the second GnRH injection and the estrus duration are not different obviously among different groups (p is more than 0.05), which indicates that the simultaneous estrus treatment of the dairy cows is not influenced by the supplementary feeding of the capsaicin.

TABLE 1 Effect of supplemental feeding of different doses of capsaicin on the ovarian follicle development and oestrus duration of cows

Note: the same index, the same row with different lower case letters shows significant difference (P <0.05)

1.2 Effect of capsaicin on the estrus, ovulation and conception rates of cows after estrus synchronization

The oestrus rate, ovulation rate, conception rate and follicle growth rate of the cows after being fed with different dosages of capsaicin are shown in table 2, and the results show that the oestrus rate, the ovulation rate, the conception rate and the follicle growth rate of the cows can be effectively improved by adding 4mg/kg of capsaicin into daily ration of the holstein cows in summer, wherein the oestrus rate of the holstein cows is 78.6 percent (22/28), the ovulation rate is 75.0 percent (21/28), the conception rate is 53.6 percent (15/28), the follicle growth rate reaches 1.6192mm/day, and the p is obviously (less than 0.05) higher than that of other dosage groups.

After capsaicin with different dosages is added into daily ration of Holstein cows for pretreatment, a GPGMH synchronous estrus program is adopted to induce the cows to estrus, and the follicular development rule after synchronous estrus treatment is researched, wherein the result is shown in figure 2, and the result shows that the follicular development comparison rule (p is more than 0.05) of a medium-dose group (4 mg/kg).

TABLE 2 oestrus rate, ovulation rate, conception rate and follicular growth rate of cows fed with different doses of capsaicin

1.3 influence of capsaicin addition to Dairy cow diet on milk production

After different dosages of capsaicin are added into daily ration of the Holstein cows, the daily milk yield of the cows is shown in table 3, and the results show that the daily milk yield of the cows of a medium dosage (4mg/kg) group is obviously higher than that of the cows of other dosage groups and a control group (P <0.05) from 20 days after the capsaicin is added. It is shown that the addition of capsaicin to the daily ration of a Holstein cow after delivery can increase the milk yield, wherein the addition of a medium dose (4mg/kg) of capsaicin per day to the daily ration from 20 days after delivery has a more pronounced effect on increasing the milk yield (see FIG. 3).

TABLE 3 daily milk yield of cows at each stage after different dosages of capsaicin

1.4 Effect of capsaicin added into daily ration on biochemical indexes of milk cow serum

The results of the serum biochemical indexes of the cows after the cows are fed with capsaicin in different doses are shown in the table 4, and the results show that the indexes of blood sugar, lipoprotein esterase and glutamic-oxalacetic transaminase of each treatment group and the control group have no significant difference (P is more than 0.05) on the day before the same estrus (namely the 29 th day of capsaicin feeding). On the day of mating (i.e., day 40 of capsaicin addition), the blood glucose levels in the medium (4mg/kg) and high (6mg/kg) dose-treated groups were significantly higher than those in the control and low dose-treated groups (P < 0.05); the level of the lipoprotein esterase of the dairy cow in each dose treatment group is obviously higher than that of a control group (P <0.05), and no obvious difference exists among the treatment groups; the aspartate aminotransferase was significantly higher in the medium dose (4mg/kg) treated group than in the low dose (2mg/kg) and control groups (P < 0.05).

Although the cows were in negative energy balance during heat stress in general, heat stress inhibited lipolysis and maintained a low blood sugar level in the cows, while lipoprotein esterase was involved in lipolysis, lipoprotein esterase in each dose group was significantly higher than that in the control group, and blood sugar in the medium dose group (4mg/kg) and the high dose group (6mg/kg) was significantly higher than that in the control group and the low dose group (2mg/kg), indicating that capsaicin was able to promote lipolysis and increase blood sugar by gluconeogenesis. A change in aspartate aminotransferase indicates a return to normal tissue metabolism. In conclusion, the chilli extract is added into daily ration in summer, so that blood circulation can be promoted, negative effects of energy negative balance can be relieved, the metabolic function of the dairy cow is maintained, and the milk yield of the dairy cow is improved.

TABLE 4 serum biochemical index of cow after feeding cow with capsaicin of different dosage

Note: the same index, shoulder-noted different lower case letters on the same row indicates significant difference (P < 0.05).

1.5 Effect of capsaicin addition to Dairy cow diet on milk composition

The results are shown in Table 5, and show that the lactose content of the high dose group (6mg/kg) and the control group is significantly higher (P <0.05) than that of the medium dose group (4mg/kg) and the low dose group (2 mg/kg); the urea nitrogen in the low dose group (2mg/kg) and the high dose group (6mg/kg) was significantly higher than in the control group (P < 0.05). On day 30 of supplementary capsaicin feeding, the lactose content in the low dose group (2mg/kg) and the high dose group (6mg/kg) was significantly higher than that in the control group (P < 0.05); there was no significant difference in total solid and urea nitrogen for each group. The milk fat rate of the low dose (2mg/kg) and medium dose (4mg/kg) groups on

days

20 and 30 after the supplementary feeding of capsaicin was significantly higher (P <0.05) than that of the control group and high dose (6mg/kg) groups. There was no significant change in milk protein rate and somatic cell number during the experiment.

TABLE 5 Effect of supplemental feeding of various doses of capsaicin on milk ingredients

Note: the same index, the same row has different lower case letters on the shoulder to indicate that the difference is obvious (P <0.05)

Example 2

A treatment method for increasing the summer reproduction rate and milk yield and quality of dairy cows by adding capsaicin into daily ration is characterized in that healthy dairy cows without reproductive tract diseases are selected and can be carried out according to the flow shown in figure 1, and the specific scheme is as follows:

selecting a cow on the 20 th day after delivery (0 day on the day of delivery), adding 1-4mg of capsaicin into each kilogram of TMR, and feeding for one month (30 days).

Day 0: on day 50 postpartum (first week), one or more healthy cows in the oestrus cycle are given monday afternoon 15: 00A first injection of GnRH was administered intramuscularly at a dose of 200. mu.g/head to induce estrus.

Day 6: on day 56 after delivery, ultrasound B examination was performed from day 6 of estrus synchronization (day before PGF2 a injection) to day 12 of ovulation (i.e. 72h after GnRH injection), and follicular development, estrus, and ovulation status were recorded.

Day 7: on postnatal day 57 (week two), monday afternoon 15: 00 intramuscular injection of PGF2 alpha at a dose of 0.5 mg/head to dissolve the corpus luteum to initiate oestrus.

Day 9: on postnatal day 59 (week two), wednesday afternoon 15: 00A second intramuscular GnRH (200. mu.g/head) was injected simultaneously with mifepristone (0.4mg/kg) to promote ovulation.

Day 10: on day 60 postpartum (week two), thursday afternoon 15: 00 artificial insemination is performed.

Day 15: on day 65 postpartum (third week), tuesday afternoon 15: 00 (i.e., day 5 after artificial insemination), the vaccinated cattle were injected intramuscularly with hCG (2000 IU/head) to promote early embryo survival.

Day 50: at day 100 postpartum (sixth week, friday) (i.e. day 40 after artificial insemination) 10 am: 00 diagnosis of pregnancy by B-ultrasound.

It should be noted that:

1. the capsaicin is added into daily ration by uniformly mixing TMR, and continuously feeding capsaicin for 30 days from 20 th day to 50 th day.

2. Rectal examination was performed before the test, and cattle with reproductive tract diseases (bilateral uterine horn with asymmetric size, follicular cyst, ovarian cyst, large uterine horn and inflammation) could not be used for the test.

3. Before each artificial insemination, alcohol is used for disinfecting the semen deposition gun, potassium permanganate disinfectant (0.1mol/L) is used for disinfecting the vulva part, and the artificial insemination personnel ensure that fingernails are cut short; the insemination technology is mastered practically, and the disposable insemination gun sleeve is used.

4. When the semen is thawed, the movement is rapid, the thawing temperature is 37.5 ℃, the sperm motility is checked by a microscope, and the sperm motility is higher than 0.3 after thawing.

5. The use of expired hormones is strictly prohibited; the injection uses a disposable syringe.

6. And (5) observing the oestrus and ovulation conditions of the cattle, and making a record.

7. Strictly performed according to a scheme.

In the operation of the synchronous estrus timing insemination scheme, because the problem of early death of the embryo is considered, the first pregnancy diagnosis is determined by observing whether the cow returns estrus or not, and in order to further improve the diagnosis accuracy, the pregnancy diagnosis is that the pregnancy condition of the cow is determined and recorded by using B ultrasonic on the 40 th day after artificial insemination.

The utilization of the invention can improve the estrus rate of reproductive cows by combining the capsaicin supplementary feeding of hybrid cows after summer and delivery with GPGMH synchronous estrus treatment, and the ovulation rate and the conception rate are respectively 78.6 percent, 75.0 percent and 53.6 percent. And the cow is treated by the traditional GPG synchronous estrus scheme, and the estrus rate, the ovulation rate and the conception rate of the cow are respectively 63.0%, 55.6% and 33.3%. In terms of production performance, the milk yield is increased by 4mg/kg (P is more than 0.05) in the medium dose group and is increased by 26.67 percent compared with the control group at 20 th and 25 th days after capsaicin addition.

The effect of daily ration prepared by adding 4mg of capsaicin into each kilogram of TMR is the best (P is less than 0.05) when the milk cow is fed with capsaicin for the second 20 days after delivery and 50 days after delivery. The postpartum cow capsaicin supplementary feeding can obviously improve the indexes of milk protein rate, milk fat rate, lactose rate and the like in 30 days, the urea nitrogen level in milk is reduced, the blood sugar level is increased, and the milk production performance of cows is improved. Therefore, the method can obviously improve the cow reproduction rate. Moreover, the invention has convenient operation, does not need estrus identification, is a programmed synchronous estrus timing insemination scheme and is convenient for popularization and application.

Claims

1. A treatment method for improving the summer reproductive rate and milk yield of dairy cows by adopting capsaicin is characterized by comprising the following steps:

s1, selecting the 20 th day of postpartum cow, adding capsaicin into the daily ration, and continuously feeding for one month, wherein the day of parturition is recorded as 0 day;

s2, on the 50 th day after delivery, marking as the 0 th day of the cow synchronous estrus treatment, injecting gonadotropin releasing hormone into the healthy cow muscle in the estrus cycle to induce estrus;

s3, day 7, intramuscular injection of treprostinil sodium to initiate estrus;

s4, on day 9, injecting gonadotropin releasing hormone for the second time, and simultaneously injecting mifepristone to promote ovulation;

s6, injecting human chorionic gonadotropin intramuscularly at day 15 after artificial insemination to promote early embryo survival;

2. The treatment method according to claim 1, wherein in step S1, the one-day supplementary feeding amount of capsaicin is 1-4mg of capsaicin per kg of TMR.

3. The treatment method according to claim 1, characterized in that the injected dose of gonadotropin releasing hormone is 200 μ g/head.

4. The process of claim 1, wherein the injection dosage of the treprostinil sodium is 0.5 mg/head in step S3.

5. The process of claim 1, wherein in step S4, the injectable dose of mifepristone is 0.4mg/kg body weight.

6. The process of claim 1, wherein in step S6, the hCG is injected in a dose of 2000 IU/head.

7. The application of the capsaicin in improving the hybridization conception rate of the dairy cows in summer and improving the milk yield is characterized in that the capsaicin is added into 1-4mg per kilogram of TMR of the dairy cows before the estrus treatment in the same period, namely 20 th day after the parturition, and is continuously fed for one month; on the 50 th day after delivery, the cow is marked as the 0 th day of the contemporaneous estrus treatment of cows, the gonadotropin releasing hormone GnRH is injected intramuscularly in the afternoon, the cloprostenol sodium PGF2 alpha is injected intramuscularly in the afternoon on the 7 th day, the gonadotropin releasing hormone GnRH is injected intramuscularly in the afternoon on the 9 th day, mifepristone is injected at the same time, the artificial insemination is performed in the afternoon on the 10 th day, the hCG is injected intramuscularly in the cattle after mating on the 15 th day, and the pregnancy condition of the cattle is determined by the type-B ultrasonic on the 50 th day.

8. The use according to claim 7, wherein the capsaicin is added at 4mg per kg TMR in cows on day 20 immediately after estrus treatment.

9. The use of claim 7, wherein the injection dose of gonadotropin releasing hormone GnRH is 200 μ g/head; the injection dosage of the PGF2 alpha is 0.5 mg/head; the injection dosage of the mifepristone is 0.4mg/kg body weight; the injection dosage of human chorionic gonadotropin hCG was 2000 IU/head.