title: Relationship between gonadal steroid hormones and vulvar bleeding in southern tamandua, Tamandua tetradactyla.
abstract: This study aimed at demonstrating the profiles of circulating gonadal steroid hormones during the estrous cycle and pregnancy in a southern tamandua (Tamandua tetradactyla). Additionally, this study clarified the relationship between vulvar bleeding and hormonal changes. The concentrations of serum progesterone (P(4)) and estradiol-17β (E(2)) were determined by enzyme immunoassays. Serum P(4) and E(2) concentrations changed cyclically and the estrous cycle length (± SD) based on the E(2) cycles was 44.3 ± 4.5 days. Vulvar bleeding started to be seen at the decreasing of P(4). The cycle length for vulvar bleeding was 43.3 ± 4.2 days. Interval from the first day of bleeding to the peak of E(2) concentration was 23.1 ± 3.1 days. Serum P(4) during pregnancy remained high and E(2) increased 8 weeks after conception and remained high until parturition. The female delivered normally after a 165 day-pregnancy period and reared the offspring well. Approximately 3 weeks after parturition, serum E(2) and P(4) cycles resumed. Visual bleeding may be useful as a real-time indicator for understanding the ovarian cycle of southern tamanduas, and estrus could be expected approximately 3 weeks after the first bleeding.
authors.affiliation: Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan. kusuda@gifu-u.ac.jp
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kusuda
authors.forename: Tomoko
authors.initials: T
authors.lastname: Endoh
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Tanaka
authors.forename: Itsuki
authors.initials: I
authors.lastname: Adachi
authors.forename: Osamu
authors.initials: O
authors.lastname: Doi
authors.forename: Junpei
authors.initials: J
authors.lastname: Kimura
mesh_terms: D000818:Animals; D004967:Estrogens / Q000097:blood*; D030762:Estrous Cycle / Q000502:physiology*; D005260:Female; D011247:Pregnancy; D011374:Progesterone / Q000097:blood*; D013997:Time Factors; D004490:Xenarthra / Q000097:blood / Q000502:physiology*
chemical_list: D004967:Estrogens; D011374:Progesterone