title: Body temperature and circulating progesterone levels before and after parturition in killer whales (Orcinus orca).
abstract: Killer whales were used to evaluate peripartum changes and interactions between body temperature and circulating progesterone concentration. Daily body temperature was measured between 0800 h and 0830 h before activity. Body temperature clearly increased during the first phase of pregnancy, and this was followed by a gradual decline until full term. The initial increase was paralleled by circulating levels of progesterone. A decrease in body temperature was first detected on day 5 (p < 0.01) before parturition, and body temperature decreased significantly every 2 days until delivery. Five days before delivery, body temperature was 0.3 C lower than the mean value during the pregnancy period, and the decrease was more marked on day 1 before delivery (0.8 C). Serum progesterone levels during pregnancy showed a general pattern of initial rapid elevation (increasing phase), followed by a gradual decline (decreasing phase) throughout the remainder of pregnancy. However, statistically significant correlations between body temperature and progesterone pattern were only found only during the increasing phase. These results suggest that monitoring body temperature variation can be considered valuable for predicting impending parturition in killer whales.
authors.affiliation: International Marine Biological Research Institute, Kamogawa Sea World, Chiba, Japan.
authors.forename: Etsuko
authors.initials: E
authors.lastname: Katsumata
authors.forename: Sukanya
authors.initials: S
authors.lastname: Jaroenporn
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Katsumata
authors.forename: Seiki
authors.initials: S
authors.lastname: Konno
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Maeda
authors.forename: Gen
authors.initials: G
authors.lastname: Watanabe
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Taya
mesh_terms: D000818:Animals; D001831:Body Temperature / Q000502:physiology*; D030762:Estrous Cycle; D005260:Female; D036801:Parturition / Q000502:physiology*; D011247:Pregnancy; D011374:Progesterone / Q000097:blood*; D050685:Whale, Killer / Q000502:physiology*
chemical_list: D011374:Progesterone