Plasma steroid profiles following follicle-stimulating hormone or equine chorionic gonadotropin injection in cows chronically treated with gonadotropin-releasing hormone agonist

• Published in: Journal of Veterinary Medical Science Vol. 64; no. 8; pp. 731 - 734
• Main Authors: "Takahashi, T. (National Inst. of Agrobiological Sciences, Tsukuba, Ibaraki (Japan)), Hirako, M, Patel, O.V, Shimizu, M, Hasegawa, Y, Domeki, I, Hashizume, K.
• Format: Journal Article
• Language: English
• Published: Japan JAPANESE SOCIETY OF VETERINARY SCIENCE 01.08.2002; Japan Science and Technology Agency
• Subjects: Animals; CATTLE; Cattle - blood; Cattle - physiology; Chorionic Gonadotropin - administration & dosage; Dinoprost - administration & dosage; eCG; Estradiol - blood; Female; Fertility Agents, Female - agonists; Follicle Stimulating Hormone - pharmacology; FSH; GNRH; Gonadotropin-Releasing Hormone - agonists; GONADOTROPINS; Gonadotropins, Equine - pharmacology; Inhibins - blood; Ovarian Follicle - drug effects; Ovarian Follicle - metabolism; Ovulation Induction - methods; Ovulation Induction - veterinary; Progesterone - blood; Random Allocation; Testosterone - blood
• ISSN: 0916-7250; 1347-7439
• DOI: 10.1292/jvms.64.731

"Plasma steroid profiles following follicle-stimulating hormone (FSH) or equine chorionic gonadotropin (eCG) injection were studied in chronically gonadotropin releasing hormone agonist (GnRH-A)-treated cows. Follicular development and irINH secretion were stimulated by FSH or eCG injection. The plasma concentrations of estradiol-17beta (E sub2) and testosterone (T) were markedly increased following eCG injection. However, significant increases of the plasma E sub2 and T concentrations were not detected in FSH-treated cows. Ovulation of developed follicles were depended on the hCG injection in both groups. These results show: 1) Follicular response to an exogenous gonadotropin is still remained, 2) Ovulation of developed follicles is induced by hCG injection and 3) FSH and eCG cause disparate plasma steroid profiles, under the influence of repeated GnRH-A treatment. "