Relationships between the ovarian status and superovulatory responses in dairy cattle

• Published in: Animal reproduction science Vol. 131; no. 3-4; pp. 123 - 128
• Main Authors: Kohram, H, Poorhamdollah, M
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01-04-2012
• Subjects: animal ovaries; Animals; Cattle; Cattle - physiology; cloprostenol; cows; dairy cattle; Dairying; Dinoprost - administration & dosage; Dinoprost - pharmacology; Drug Administration Schedule; Embryo; estrous cycle; Estrous Cycle - physiology; Estrus Synchronization - drug effects; Female; Follicle Stimulating Hormone - administration & dosage; Follicle Stimulating Hormone - pharmacology; Folltropin-V; Holstein; luteolysis; Ovarian Follicle - drug effects; Ovarian Follicle - physiology; Oxytocics - administration & dosage; Oxytocics - pharmacology; Superovulation; Superovulation - drug effects; ultrasonics; Ultrasonography; Japan; Embryo; Cattle; Folltropin-V; Superovulation; Ultrasonography
• ISSN: 0378-4320; 1873-2232
• DOI: 10.1016/j.anireprosci.2012.03.004

The aim of this study was to determine the influence of follicular profiles over 4 days prior to superovulation on superovulatory responses. Eighty-eight Holstein cows were synchronized by two prostaglandin F2α injections given 11 days apart and conventionally superovulated between days 8 and 12 of the estrous cycle with 400mg Folltropin-V given in decreasing doses over 4 days. Luteolysis was induced by 2 im injections of cloprostenol (2ml) with the sixth and seventh injections of Folltropin-V. The ovaries of all cows were examined by ultrasonography with a real-time linear scanning ultrasound diagnostic system (Ls-300-A: Tokyo Keiki Co., Tokyo, Japan; 7.5MHz Transducer) on days −3, −2, −1, 0 (initiation day of the superovulatory treatment=day 0). Data were analyzed by the GLM procedure of the SAS. Animals with a greater diameter of the largest follicle (F1; 13.4 vs 9.8 and 10.1mm; p<0.007) and with a greater difference in the diameter of the first and second largest follicles (7.6 vs 4.5 and 3.8mm; p<0.001) had the greater superovulatory response and produced the greater number of quality I embryos. In conclusion, the diameter of the F1 and the F1–F2 follicles were higher over a 4-day period prior to superovulation in animals yielding a high than a medium and a low number of quality I and I+II embryos.