Regulation of estrus and ovulation in gilts

• US 6,028,057 A
• Filed: 02/19/1998
• Issued: 02/22/2000
• Est. Priority Date: 02/19/1998
• Status: Expired due to Fees

• Current Assignee: Thorne Bioscience LLC
• Original Assignee: Thorne Bioscience LLC
• Inventors: Burns, Patrick J.
• Primary Examiner(s): Davenport, Avis M.
• Application Number:
  US09/026,463
• Time in Patent Office: 733 Days
• Field of Search: 514/12, 530/324
• US Class Current: 424/430
• CPC Class Codes: A61K 2300/00 Mixtures or combinations of active ingredients, wherein at least one active ingredient is fully defined in groups A61K31/00 - A61K41/00
• CPC Class Codes: A61K 31/565 not substituted in position 17 beta by a carbon atom, e.g. estrane, estradiol
• CPC Class Codes: A61K 31/566 having an oxo group in position 17, e.g. estrone
• CPC Class Codes: A61K 38/09 Luteinising hormone-releasing hormone [LHRH] , i.e. Gonadotropin-releasing hormone [GnRH]; Related peptides
• CPC Class Codes: A61K 38/24 Follicle-stimulating hormone [FSH]; Chorionic gonadotropins, e.g. HCG; Luteinising hormone [LH]; Thyroid-stimulating hormone [TSH]
• CPC Class Codes: A61K 47/26 Carbohydrates, e.g. sugar alcohols, amino sugars, nucleic acids, mono-, di- or oligo-saccharides; Derivatives thereof, e.g. polysorbates, sorbitan fatty acid esters or glycyrrhizin
• CPC Class Codes: A61K 9/0019 Injectable compositions; Intramuscular, intravenous, arterial, subcutaneous administration; Compositions to be administered through the skin in an invasive manner non-active ingredients are additionally classified in A61K47/00
• CPC Class Codes: A61K 9/0024 Solid, semi-solid or solidifying implants, which are implanted or injected in body tissue compositions for intravenous administration, normal injectable solutions or dispersions for, e.g. subcutaneous administration A61K9/0019; brain implants A61K9/0085; (coated) prostheses, catheters or stents A61L
• CPC Class Codes: A61K 9/1647 Polyesters, e.g. poly(lactide-co-glycolide)
• CPC Class Codes: A61P 15/00 Drugs for genital or sexual disorders for disorders of sex hormones A61P5/24; Contraceptives

Abstract

Controlled release compositions and methods for inducing pseudopregnancy in gilts and sows are disclosed. In the preferred embodiment, the formulation includes polylactide microspheres releasing estradiol 17β at physiologically useful levels over a period of time between five and thirty days. Following induction of pseudopregnancy, the pseudopregnancy can be terminated and estrus induced by administration of a compound such as PGF2α. The advantages of inducing pseudopregnancy followed by induction of estrus are that the breeding patterns of large numbers of gilts and sows can be controlled.

Claims

1. A method for inducing pseudopregnancy in fertile female pigs comprising administering to the pigs an effective amount of a compound that induces pseudopregnancy in a biodegradable controlled release formulation.

2. The method of claim 1 further comprising chemically inducing puberty in the gilts prior to induction of pseudopregnancy.

3. The method of claim 2 wherein the puberty was induced by administration of a combination of pregnant mare'"'"'s serum gonadotrophin and human chorionic gonadotropin.

4. The method of claim 1 wherein the formulation comprises microparticles that release physiologically useful levels of the compound in a controlled fashion over a period of time between 5 and 30 days.

5. The method of claim 4 wherein the microparticles comprise a biodegradable polymer.

6. The method of claim 5 wherein the polymer is selected from the group consisting of polyhydroxy acids, polyorthoesters, polylactones, polycarbonates, polyphosphazenes, polysaccharides, proteins, polyanhydrides, copolymers thereof and blends thereof.

7. The method of claim 6 wherein the polymer is selected from the group consisting of polylactic acid, polyglycolic acid, and poly lactic-co-glycolic acid.

8. The method of claim 1 wherein the compound is selected from the group consisting of 17β

-estradiol, mono esters of estradiol, diesters of estradiol, mono of estradiol, diethers of estradiol, alkyl derivatives at the 17 position of estradiol, conjugated equine estrogens, estrone, piperazine estrone sulfate, estriol, estriol succinate polyestrol phosphate, 17α

-estradiol, and mixtures thereof.

9. The method of claim 1 wherein the compound is selected from the group consisting of estradiol, estrone, estriol, esters thereof and mixtures thereof.

10. The method of claim 1, further comprising administering a composition that induces estrus while the gilt or sow is pseudopregnant.

11. The method of claim 10 further comprising artificially inseminating the gilt or sow.

19. The method of claim 1 wherein the formulation comprises an in situ gelling system.

20. The method of claim 19 wherein the formulation comprises sucrose acetate isobutyrate.

12. A composition for inducing pseudopregnancy in a gilt or sow comprising a biodegradable controlled release formulation of a compound that induces pseudopregnancy in a gilt or sow.

13. The composition of claim 12, wherein the formulation comprises microparticles.

14. The composition of claim 12 wherein the compound is selected from the group consisting of 17β

-estradiol, mono esters of estradiol, diesters of estradiol, mono of estradiol, diethers of estradiol, alkyl derivatives at the 17 position of estradiol, conjugated equine estrogens, estrone, piperazine estrone sulfate, estriol, estriol succinate polyestrol phosphate, 17 α

-estradiol and mixtures thereof.

15. The composition of claim 14 wherein the compound is selected from the group consisting of estradiol 17β

, estrone, estriol, esters thereof and mixtures thereof.

16. The composition of claim 13 wherein the microparticles comprise a polymer selected from the group consisting of polyhydroxy acids, polyorthoesters, polylactones, polycarbonates, polyphosphazenes, polysaccharides, proteins, polyanhydrides, copolymers thereof and blends thereof.

17. The composition of claim 16 wherein the polymer is selected from the group consisting of polylactic acid, polyglycolic acid, and polylactic-co-glycolic acid.

18. The composition of claim 13 wherein the compound is estradiol 17β

and the polymer is polylactic acid.

21. The composition of claim 12 wherein the formulation comprises an in situ gelling system.

22. A method for inducing pseudopregnancy in fertile female pigs comprising administering to the pigs an effective amount of a compound that induces pseudopregnancy in an implantable controlled release formulation, which can be removed from the pigs following release of the compound.

23. A device for inducing pseudopregnancy in a gilt or sow comprising an implantable controlled release formulation of a compound that induces pseudopregnancy, wherein the device can be removed from the pigs following release of the compound.

24. The device of claim 23 wherein the formulation is selected from the group consisting of cervical rings, vaginal rings, sponges, and other intravaginal implants.