title: Relationships between the ovarian status and superovulatory responses in dairy cattle.
abstract: 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 F(2)α injections given 11 days apart and conventionally superovulated between days 8 and 12 of the estrous cycle with 400 mg Folltropin-V given in decreasing doses over 4 days. Luteolysis was induced by 2 im injections of cloprostenol (2 ml) 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; 7.5 MHz 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 10.1 mm; p<0.007) and with a greater difference in the diameter of the first and second largest follicles (7.6 vs 4.5 and 3.8 mm; 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.
authors.affiliation: Department of Animal Science, Faculty College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran. kohram@can.ut.ac.ir
authors.forename: H
authors.initials: H
authors.lastname: Kohram
authors.forename: M
authors.initials: M
authors.lastname: Poorhamdollah
mesh_terms: D000818:Animals; D002417:Cattle / Q000502:physiology*; D003612:Dairying; D015237:Dinoprost / Q000008:administration & dosage / Q000494:pharmacology*; D004334:Drug Administration Schedule; D030762:Estrous Cycle / Q000502:physiology*; D004973:Estrus Synchronization / Q000187:drug effects; D005260:Female; D005640:Follicle Stimulating Hormone / Q000008:administration & dosage / Q000494:pharmacology; D006080:Ovarian Follicle / Q000187:drug effects / Q000502:physiology*; D010120:Oxytocics / Q000008:administration & dosage / Q000494:pharmacology*; D013480:Superovulation / Q000187:drug effects*
chemical_list: D010120:Oxytocics; D005640:Follicle Stimulating Hormone; D015237:Dinoprost