Compound progesterone sponge for synchronizing estrus of sheep and preparation and application thereof

Abstract

This invention discloses a compound progesterone sponge suppository for sheep estrus synchronization, its preparation, and its application. The sponge suppository comprises a progesterone sponge suppository and triptorelin; the mass ratio of triptorelin to the progesterone sponge suppository is (0.1~2.0):40. The preparation method of the sponge suppository includes: dissolving triptorelin in sterile water to obtain a drug solution; injecting the drug solution into the progesterone sponge suppository, drying, and sterilizing. This invention solves the problems of complex operation and poor stability in existing technologies. This invention combines the progesterone sponge suppository with the GnRH agonist triptorelin, significantly improving estrus synchronization, estrus conception rate, ovulation rate, and lambing rate in sheep undergoing timed insemination. Specifically, the conception rate and lambing rate increased by 28.6% and 20%, respectively. It also improves endometrial receptivity in sheep and increases the pregnancy rate of sheep embryo transfer, bringing significant economic benefits to farmers and is suitable for industrial promotion.

Description

Technical Field

[0001] This invention belongs to the field of sheep breeding technology, specifically relating to a compound progesterone sponge suppository for sheep to synchronize estrus and its preparation and application. Background Technology

[0002] Implementing estrus synchronization and timed insemination techniques is an important measure to improve the reproductive efficiency of sheep and goats. Current research utilizes exogenous hormones to control and alter the activity patterns of ewes' ovaries, thereby enabling them to synchronize estrus, ovulation, mating, lambing, and market entry within a predetermined timeframe. This will fundamentally change the traditional indiscriminate mating breeding model in sheep flocks, eliminating the need for estrus detection, reducing labor costs, increasing lambing and reproductive rates, achieving "three births in two years," and also facilitating disease control and maximizing the mating efficiency of superior rams.

[0003] Currently, existing literature 1 (CN115645516A) discloses a sheep estrus synchronization suppository and its preparation method, belonging to the field of sheep breeding technology. By combining fluoroprogesterone, human chorionic gonadotropin, and cloprostenol, and using ceftiofur and penicillin, it overcomes the problem that the effect of existing estrus synchronization suppositories applied in Xinjiang is insufficient. The resulting compound hormone can effectively improve the estrus synchronization rate and concentrate the estrus time within 24 hours after suppository removal, avoiding additional manpower and material costs and making management easier. The estrus synchronization rate within 72 hours can reach 100%. The sponge suppository can also effectively improve the late conception situation, with a conception rate of 95.00% and a lambing rate of 201.82% after application. However, literature 1 requires strict control of the insemination time within 72 hours after suppository removal, which has high technical requirements; long-term use of antibiotics may lead to bacterial resistance and pose a risk of drug residues.

[0004] Existing literature 2 (CN117100843A) relates to a pharmaceutical composition and its method and application for improving the pregnancy rate of cashmere goats. The technical solution uses hormonal drugs such as pregnant mare serum gonadotropin and cloprostenol in combination with nutritional regulation methods to improve the conception rate before and after mating through injection or feeding. However, literature 2 requires precise control of the timing and dosage of hormone use, with a strict operating window; the mechanism of action is not clear enough, and there is a lack of targeted research on the special physiological characteristics of cashmere goats; it relies solely on drug stimulation while ignoring comprehensive factors of feeding and management, resulting in poor stability of the effect; there is the problem of hormone residue, affecting the safety of livestock products; the applicability varies greatly among cashmere goats of different breeds, ages, and body conditions, making it difficult to standardize and promote; long-term repeated use may lead to endocrine disorders in ewes and reduce their natural reproductive capacity. Summary of the Invention

[0005] The purpose of this invention is to provide a compound progesterone sponge suppository for sheep to synchronize estrus, and its preparation and application. It solves the problems of complicated operation and poor conception rate stability in the existing technology. The compound progesterone sponge suppository can effectively improve the estrus synchronization, estrus conception rate and lambing rate of sheep, and concentrate the estrus time within 48h to 60h after suppository removal, avoiding additional manpower and material costs, and making it more conducive to management.

[0006] To achieve the above objectives, the present invention provides a compound progesterone sponge suppository for sheep to synchronize estrus, the sponge suppository comprising: progesterone sponge suppository and triptorelin; The mass ratio of triptorelin to the progesterone sponge plug is (0.1~2.0):40.

[0007] Preferably, the mass ratio of triptorelin to the progesterone sponge plug is (0.3~1.0):40.

[0008] Preferably, the mass ratio of triptorelin to the progesterone sponge plug is 0.1:10.

[0009] This invention provides a method for preparing the sponge plug as described above, the method comprising: Dissolve triptorelin in sterile water to obtain a drug solution; inject the drug solution into a progesterone sponge plug, dry, and sterilize.

[0010] Preferably, the mass-to-volume ratio of triptorelin to sterile water is (30~60) mg : (100~140) mL.

[0011] Preferably, the mass-to-volume ratio of triptorelin to sterile water is (40~50) mg : (110~125) mL.

[0012] Preferably, the drying temperature is 40°C and the drying time is 3 hours.

[0013] Preferably, the sterilization method is gamma irradiation sterilization, with an irradiation dose of 15 kGrey.

[0014] This invention provides an application of the sponge plug as described above in animal breeding.

[0015] More preferably, the animal is a sheep.

[0016] This invention relates to a compound progesterone sponge suppository for sheep estrus synchronization, its preparation, and its application. It solves the problems of complex operation and poor stability in existing technologies, and has the following advantages: 1. This invention combines progesterone sponge suppositories with the GnRH agonist triptorelin, which can significantly improve estrus synchronization, conception rate, and lambing rate in sheep undergoing timed insemination and estrus synchronization. It can also improve endometrial receptivity and increase embryo transfer pregnancy rates in sheep. However, GnRH agonists have very short half-lives (e.g., triptorelin's half-life is only 50 minutes), requiring large doses or multiple injections to ensure efficacy. This invention loads 200µg of the GnRH agonist triptorelin into progesterone sponge suppositories. The sustained-release effect of the sponge and the slow absorption by the endometrium prolong the half-life and efficacy of triptorelin. This compound progesterone suppository improves estrus synchronization, timed insemination, superovulation, and embryo transfer in sheep while saving labor and costs.

[0017] 2. The compound progesterone sponge suppository obtained in this invention can effectively improve the estrus synchronization rate and estrus synchronization of sheep, concentrating the estrus time within 48-60 hours after suppository removal, avoiding additional manpower and material costs, and making management more convenient. The estrus synchronization rate within 72 hours can reach 98%. The compound progesterone sponge suppository, through the slow-release effect of the sponge, downregulates pituitary secretion activity, prevents premature occurrence of endogenous luteinizing hormone peaks, and promotes the convergence of follicle diameters among more follicles in the same follicular wave. After synchronization, appropriate doses of exogenous gonadotropins are administered to stimulate follicle development, enabling more follicles to develop into dominant follicles, resulting in more mature oocytes. The conception rate and lambing rate are increased by 28.6% and 20%, respectively, bringing significant economic benefits to farmers and making it suitable for industrial promotion. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the comparative operation in Experiment Example 1 of the present invention.

[0019] Figure 2 This is a schematic diagram of the comparative operation in Experiment Example 2 of the present invention. Detailed Implementation

[0020] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Example 1 A method for preparing a compound progesterone sponge suppository for sheep to synchronize estrus, the method comprising: Accurately weigh 48 mg of triptorelin (Zhejiang Paitai Biotechnology Co., Ltd.), add 120 mL of sterile water, mix well to obtain triptorelin solution; then take 240 progesterone sponge suppositories (Ningbo Second Hormone Factory), use a 1 mL syringe to draw triptorelin solution and inject it into the progesterone sponge suppositories, injecting 0.5 mL of triptorelin solution into each progesterone sponge suppository, then dry in a 40℃ oven for 3 hours and package (in a transparent plastic bag and heat-sealed), and sterilize by irradiation with 15 kGy gamma rays for 20 minutes to obtain compound progesterone sponge suppositories.

[0022] Comparative Example 1 The preparation method of a progesterone sponge suppository is basically the same as that in Example 1, except that: Do not add triptorelin.

[0023] Experimental Example 1 The compound progesterone sponge suppositories prepared in Example 1 and the progesterone sponge suppositories were used and designated as Experimental Group I and Experimental Group II, respectively. Figure 1 The diagram shows the comparative operation of Experiment Example 1 of this invention. The compound progesterone sponge suppository is the product prepared in Example 1; the progesterone sponge suppository is the product of Comparative Example 1; and PMSG is pregnant mare serum gonadotropin. In Experiment Group I, the compound progesterone sponge suppository prepared in Example 1 was inserted into the vagina of 120 Kazakh sheep (from a sheep farm in Zhaosu County, Ili Prefecture; healthy, disease-free ewes over 1.5 years old, all in moderate condition, and without reproductive system diseases) and fixed near the cervix. The suppository was in place for 12 days. If any sheep lost the suppository, it was promptly replaced. At the time of suppository removal (12 days), each sheep was injected with 400 units of pregnant mare serum gonadotropin (PMSG). Estrus rates were recorded at 24-36 hours, 36-48 hours, and 48-60 hours after suppository removal. Estrus in ewes was identified using rams. If a ewe approached a ram, stood still, and accepted mounting, it indicated estrus, and the ewe was marked. Both experimental group II and experimental group I underwent tethering on the same day, the only difference being that progesterone-laced sponge tethers were used. The number of sheep exhibiting estrus synchronously and the estrus rate in each group were recorded, and the results are shown in Table 1 below.

[0024] Table 1. Results of estrus synchronization treatment with compound progesterone sponge suppositories (unit: suppositories) ; As shown in Table 1, the use of compound progesterone sponge suppositories for estrus synchronization resulted in significantly higher estrus synchronization, with estrus occurring within 48-60 hours after suppository removal. In contrast, estrus in the progesterone sponge suppository group was more dispersed, which is not conducive to management in industrial applications and would increase additional human and material costs.

[0025] Artificial insemination was performed on 240 ewes in the above experiment at 52h and 64h (14d) after tether removal. The semen was obtained from healthy adult Texel rams with a sperm motility of not less than 0.7 and an effective sperm count of not less than 50 million per ewe per insemination. After insemination, the ewes were fed normally. The conception rate was calculated by ultrasound 45 days after insemination, and the lambing rate and farrowing rate were calculated 160 days later. The conception rate = number of ewes that conceived / number of ewes that were bred × 100%; the farrowing rate = number of ewes that gave birth / number of ewes that conceived × 100%; and the lambing rate = number of lambs born / number of ewes that gave birth × 100%. The results are shown in Table 2 below.

[0026] Table 2. Conception and lambing rates in ewes with estrus synchronization treated with compound progesterone sponge suppositories (unit: ewes) ; As shown in Table 2, when the number of ewes receiving insemination is the same, the conception rate of the compound progesterone sponge suppository prepared in Example 1 increased from 63.8% to 81.4%, an increase of 28.6%; the lambing rate reached 1.21, an increase of 20%.

[0027] Experiment Example 2 The compound progesterone sponge suppositories prepared in Example 1 were used together with the progesterone sponge suppositories, and were designated as experimental group A and experimental group B, respectively. Figure 2 The diagram shows the comparative operation of Experimental Example 2 of the present invention. The compound progesterone sponge suppository is the product prepared in Example 1; the progesterone sponge suppository is the product of Comparative Example 1; PMSG is pregnant mare serum gonadotropin; and PG is prostaglandin. In Experimental Group A, the compound progesterone sponge suppository prepared in Example 1 was inserted into the vagina of 150 healthy, disease-free ewes (over 2.5 years old, of moderate condition, and without reproductive system diseases) and fixed near the cervix. The total duration of suppository placement was 12 days. At 8:00 AM on the 11th day after suppository placement, each sheep was intramuscularly injected with 330 units of pregnant mare serum gonadotropin (PMSG) and 0.1 mg of prostaglandin (PG). The suppository was removed at 8:00 AM on the 12th day after suppository placement, and the reproductive tract was cleaned with physiological saline. Artificial insemination was performed via vaginal insemination at 8:00 AM and 6:00 PM on the 14th day after suppository placement. Experimental Group B underwent suppository placement on the same day as Experimental Group A, the only difference being the use of progesterone sponge suppositories.

[0028] Semen was obtained from healthy adult Australian white rams with a sperm motility of not less than 0.7. Each ewe had an effective sperm count of not less than 50 million per insemination. After insemination, the ewes were fed normally. The conception rate was calculated by ultrasound 45 days after insemination, and the lambing rate and farrowing rate were calculated 160 days later. Conception rate = number of ewes that conceived / number of ewes that were bred × 100%; farrowing rate = number of ewes that gave birth / number of ewes that conceived × 100%; lambing rate = number of lambs born / number of ewes that gave birth × 100%. The results are shown in Table 3 below.

[0029] Table 3. Conception and lambing rates in ewes with estrus synchronization treated with compound progesterone sponge suppositories (unit: ewes) ; As shown in Table 3, the compound progesterone sponge suppository provided by the present invention can significantly improve the conception rate and lambing rate of sheep with synchronized estrus and timed insemination.

[0030] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A compound progesterone sponge suppository for sheep to synchronize estrus, characterized in that, The sponge plug contains: a progesterone sponge plug and triptorelin; The mass ratio of triptorelin to the progesterone sponge plug is (0.1~2.0):

40.

2. The sponge plug according to claim 1, characterized in that, The mass ratio of triptorelin to the progesterone sponge plug is (0.3~1.0):

40.

3. The sponge plug according to claim 1, characterized in that, The mass ratio of triptorelin to the progesterone sponge plug is 0.1:

10.

4. A method for preparing a sponge plug as described in any one of claims 1 to 3, characterized in that, The method includes: Dissolve triptorelin in sterile water to obtain a drug solution; inject the drug solution into a progesterone sponge plug, dry, and sterilize.

5. The sponge plug according to claim 4, characterized in that, The mass-to-volume ratio of triptorelin to sterile water is (30~60) mg : (100~140) mL.

6. The sponge plug according to claim 4, characterized in that, The mass-to-volume ratio of triptorelin to sterile water is (40~50) mg : (110~125) mL.

7. The sponge plug according to claim 4, characterized in that, The drying temperature is 40°C and the time is 3 hours.

8. The sponge plug according to claim 4, characterized in that, The sterilization method is gamma ray irradiation sterilization, with an irradiation dose of 15 kGrey.

9. The application of a sponge plug as described in any one of claims 1 to 3 in animal breeding.

10. The application according to claim 9, characterized in that, The animal in question is a sheep.

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