title: Magnetic Resonance Imaging of Ovarian Activity in Microminipigs Showing Normal Estrous Cycles.
abstract: We investigated whether magnetic resonance imaging (MRI) might be applicable to evaluation of the ovarian activity of microminipigs. Firstly, using three mature microminipigs, we confirmed ovarian position and morphology by laparotomy or laparoscopy, and then acquired MRI images in various patterns to determine the most suitable condition for the acquisition. Next, using four microminipigs, we performed daily MRI, starting 10 days after ovulation and ending 10 days after the subsequent ovulation, as the starting day of standing estrus was taken as day 0. While the ovarian structure could not be discriminated on T1-weighted imaging, it was possible to confirm the follicles during estrus as hyperintense regions on T2-weighted imaging. With chronological MRI, 3-5 follicles were visible on T2-weighted imaging during the interval from day -2 to day 1, and their size immediately prior to ovulation was 3-5 mm. However, confirmation of the presence of small follicles and the corpus luteum was difficult.
authors.affiliation: United Graduate School of Veterinary Science, Gifu University, Gifu, Japan.
authors.forename: Masami
authors.initials: M
authors.lastname: Maeda
authors.affiliation: Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Takashima
authors.affiliation: United Graduate School of Veterinary Science, Gifu University, Gifu, Japan Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan takasu@gifu-u.ac.jp.
authors.forename: Masaki
authors.initials: M
authors.lastname: Takasu
authors.affiliation: United Graduate School of Veterinary Science, Gifu University, Gifu, Japan Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Mori
authors.affiliation: Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan.
authors.forename: Nozomi
authors.initials: N
authors.lastname: Goto
authors.affiliation: United Graduate School of Veterinary Science, Gifu University, Gifu, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Matsubara
authors.affiliation: United Graduate School of Veterinary Science, Gifu University, Gifu, Japan.
authors.forename: Julio
authors.initials: J
authors.lastname: Almunia
authors.affiliation: Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan.
authors.forename: Noriaki
authors.initials: N
authors.lastname: Imaeda
authors.affiliation: Department of Molecular Life Science, Division of Basic Medical Science and Molecular Medicine, Tokai University School of Medicine, Kanagawa, Japan.
authors.forename: Asako
authors.initials: A
authors.lastname: Ando
authors.affiliation: United Graduate School of Veterinary Science, Gifu University, Gifu, Japan Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Kitagawa
mesh_terms: D000818:Animals; D003338:Corpus Luteum / Q000502:physiology; D030762:Estrous Cycle / Q000502:physiology*; D005260:Female; D010535:Laparoscopy / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D006080:Ovarian Follicle / Q000502:physiology*; D010060:Ovulation / Q000502:physiology; D013552:Swine; D013556:Swine, Miniature
keywords: MRI; estrus; microminipig; ovary