Cloprostenol: A synthetic prostaglandin F2alpha analog. The compound has luteolytic effects and is used for the synchronization of estrus in cattle.Prostaglandins F, Synthetic: Analogs or derivatives of prostaglandins F that do not occur naturally in the body. They do not include the product of the chemical synthesis of hormonal PGF.Prostaglandins, Synthetic: Compounds obtained by chemical synthesis that are analogs or derivatives of naturally occurring prostaglandins and that have similar activity.Luteolysis: Degradation of CORPUS LUTEUM. In the absence of pregnancy and diminishing trophic hormones, the corpus luteum undergoes luteolysis which is characterized by the involution and cessation of its endocrine function.Corpus Luteum: The yellow body derived from the ruptured OVARIAN FOLLICLE after OVULATION. The process of corpus luteum formation, LUTEINIZATION, is regulated by LUTEINIZING HORMONE.Luteolytic Agents: Chemical compounds causing LUTEOLYSIS or degeneration.Estrus Synchronization: Occurrence or induction of ESTRUS in all of the females in a group at the same time, applies only to non-primate mammals with ESTROUS CYCLE.Progesterone: The major progestational steroid that is secreted primarily by the CORPUS LUTEUM and the PLACENTA. Progesterone acts on the UTERUS, the MAMMARY GLANDS and the BRAIN. It is required in EMBRYO IMPLANTATION; PREGNANCY maintenance, and the development of mammary tissue for MILK production. Progesterone, converted from PREGNENOLONE, also serves as an intermediate in the biosynthesis of GONADAL STEROID HORMONES and adrenal CORTICOSTEROIDS.Dinoprost: A naturally occurring prostaglandin that has oxytocic, luteolytic, and abortifacient activities. Due to its vasocontractile properties, the compound has a variety of other biological actions.Estrus: The period in the ESTROUS CYCLE associated with maximum sexual receptivity and fertility in non-primate female mammals.Labor Stage, Third: The final period of OBSTETRIC LABOR that is from the expulsion of the FETUS to the expulsion of the PLACENTA.Callithrix: A genus of the subfamily CALLITRICHINAE occurring in forests of Brazil and Bolivia and containing seventeen species.Ovulation: The discharge of an OVUM from a rupturing follicle in the OVARY.Gonadotropins, Equine: Gonadotropins secreted by the pituitary or the placenta in horses. This term generally refers to the gonadotropins found in the pregnant mare serum, a rich source of equine CHORIONIC GONADOTROPIN; LUTEINIZING HORMONE; and FOLLICLE STIMULATING HORMONE. Unlike that in humans, the equine LUTEINIZING HORMONE, BETA SUBUNIT is identical to the equine choronic gonadotropin, beta. Equine gonadotropins prepared from pregnant mare serum are used in reproductive studies.Buserelin: A potent synthetic analog of GONADOTROPIN-RELEASING HORMONE with D-serine substitution at residue 6, glycine10 deletion, and other modifications.Abortion, Veterinary: Premature expulsion of the FETUS in animals.Oxytocics: Drugs that stimulate contraction of the myometrium. They are used to induce LABOR, OBSTETRIC at term, to prevent or control postpartum or postabortion hemorrhage, and to assess fetal status in high risk pregnancies. They may also be used alone or with other drugs to induce abortions (ABORTIFACIENTS). Oxytocics used clinically include the neurohypophyseal hormone OXYTOCIN and certain prostaglandins and ergot alkaloids. (From AMA Drug Evaluations, 1994, p1157)Luteal Phase: The period in the MENSTRUAL CYCLE that follows OVULATION, characterized by the development of CORPUS LUTEUM, increase in PROGESTERONE production by the OVARY and secretion by the glandular epithelium of the ENDOMETRIUM. The luteal phase begins with ovulation and ends with the onset of MENSTRUATION.Sheep: Any of the ruminant mammals with curved horns in the genus Ovis, family Bovidae. They possess lachrymal grooves and interdigital glands, which are absent in GOATS.Cattle: Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.Prostaglandins F: (9 alpha,11 alpha,13E,15S)-9,11,15-Trihydroxyprost-13-en-1-oic acid (PGF(1 alpha)); (5Z,9 alpha,11,alpha,13E,15S)-9,11,15-trihydroxyprosta-5,13-dien-1-oic acid (PGF(2 alpha)); (5Z,9 alpha,11 alpha,13E,15S,17Z)-9,11,15-trihydroxyprosta-5,13,17-trien-1-oic acid (PGF(3 alpha)). A family of prostaglandins that includes three of the six naturally occurring prostaglandins. All naturally occurring PGF have an alpha configuration at the 9-carbon position. They stimulate uterine and bronchial smooth muscle and are often used as oxytocics.Abortion, Induced: Intentional removal of a fetus from the uterus by any of a number of techniques. (POPLINE, 1978)Relaxin: A water-soluble polypeptide (molecular weight approximately 8,000) extractable from the corpus luteum of pregnancy. It produces relaxation of the pubic symphysis and dilation of the uterine cervix in certain animal species. Its role in the human pregnant female is uncertain. (Dorland, 28th ed)Oxytocin: A nonapeptide hormone released from the neurohypophysis (PITUITARY GLAND, POSTERIOR). It differs from VASOPRESSIN by two amino acids at residues 3 and 8. Oxytocin acts on SMOOTH MUSCLE CELLS, such as causing UTERINE CONTRACTIONS and MILK EJECTION.Insemination, Artificial: Artificial introduction of SEMEN or SPERMATOZOA into the VAGINA to facilitate FERTILIZATION.Pregnancy: The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.Luteinizing Hormone: A major gonadotropin secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Luteinizing hormone regulates steroid production by the interstitial cells of the TESTIS and the OVARY. The preovulatory LUTEINIZING HORMONE surge in females induces OVULATION, and subsequent LUTEINIZATION of the follicle. LUTEINIZING HORMONE consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH and FSH), but the beta subunit is unique and confers its biological specificity.Ovarian Follicle: An OOCYTE-containing structure in the cortex of the OVARY. The oocyte is enclosed by a layer of GRANULOSA CELLS providing a nourishing microenvironment (FOLLICULAR FLUID). The number and size of follicles vary depending on the age and reproductive state of the female. The growing follicles are divided into five stages: primary, secondary, tertiary, Graafian, and atretic. Follicular growth and steroidogenesis depend on the presence of GONADOTROPINS.Estradiol: The 17-beta-isomer of estradiol, an aromatized C18 steroid with hydroxyl group at 3-beta- and 17-beta-position. Estradiol-17-beta is the most potent form of mammalian estrogenic steroids.Dictionaries, MedicalDictionaries as Topic: Lists of words, usually in alphabetical order, giving information about form, pronunciation, etymology, grammar, and meaning.Marketing: Activity involved in transfer of goods from producer to consumer or in the exchange of services.Research Report: Detailed account or statement or formal record of data resulting from empirical inquiry.Salts: Substances produced from the reaction between acids and bases; compounds consisting of a metal (positive) and nonmetal (negative) radical. (Grant & Hackh's Chemical Dictionary, 5th ed)Foundations: Organizations established by endowments with provision for future maintenance.Dietetics: The application of nutritional principles to regulation of the diet and feeding persons or groups of persons.Chemical Safety: Risk or hazard associated with the handling and use of chemicals.Chloral Hydrate: A hypnotic and sedative used in the treatment of INSOMNIA.Hazardous Substances: Elements, compounds, mixtures, or solutions that are considered severely harmful to human health and the environment. They include substances that are toxic, corrosive, flammable, or explosive.Sodium: A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.Veterinary Medicine: The medical science concerned with the prevention, diagnosis, and treatment of diseases in animals.China: A country spanning from central Asia to the Pacific Ocean.Veterinary Drugs: Drugs used by veterinarians in the treatment of animal diseases. The veterinarian's pharmacological armamentarium is the counterpart of drugs treating human diseases, with dosage and administration adjusted to the size, weight, disease, and idiosyncrasies of the species. In the United States most drugs are subject to federal regulations with special reference to the safety of drugs and residues in edible animal products.Education, Veterinary: Use for general articles concerning veterinary medical education.Schools, Veterinary: Educational institutions for individuals specializing in the field of veterinary medicine.Physiological Processes: The functions and activities of living organisms that support life in single- or multi-cellular organisms from their origin through the progression of life.Telefacsimile: A telecommunication system combining the transmission of a document scanned at a transmitter, its reconstruction at a receiving station, and its duplication there by a copier.Legislation, Food: Laws and regulations concerned with industrial processing and marketing of foods.Receptors, Prostaglandin: Cell surface receptors that bind prostaglandins with high affinity and trigger intracellular changes which influence the behavior of cells. Prostaglandin receptor subtypes have been tentatively named according to their relative affinities for the endogenous prostaglandins. They include those which prefer prostaglandin D2 (DP receptors), prostaglandin E2 (EP1, EP2, and EP3 receptors), prostaglandin F2-alpha (FP receptors), and prostacyclin (IP receptors).Health Food: A non-medical term defined by the lay public as a food that has little or no preservatives, which has not undergone major processing, enrichment or refinement and which may be grown without pesticides. (from Segen, The Dictionary of Modern Medicine, 1992)Receptors, Prostaglandin E: Cell surface receptors which bind prostaglandins with a high affinity and trigger intracellular changes which influence the behavior of cells. Prostaglandin E receptors prefer prostaglandin E2 to other endogenous prostaglandins. They are subdivided into EP1, EP2, and EP3 types based on their effects and their pharmacology.Receptors, Prostaglandin E, EP2 Subtype: A subtype of prostaglandin E receptors that specifically couples to GS ALPHA GTP-BINDING PROTEIN SUBUNITS and subsequently activates ADENYLYL CYCLASES.