title: Ovarian synchronisation in wood bison (Bison bison athabascae) during the anovulatory season.
abstract: Two experiments were performed in wood bison during the anovulatory season to establish an effective protocol for ovarian synchronisation. In an untreated control phase, bison cows (n=19) were examined daily to establish the interval to new follicular wave emergence (4.9±0.7 days) for the purposes of comparison with the experimental treatments. In Experiment 1, bison were treated by transvaginal ultrasound-guided follicular ablation (n=9) or with 2mg, i.m., 17β-oestradiol (n=10). In Experiment 2, bison were treated by follicular ablation (n=9) or with 2mg, i.m., 17β-oestradiol +100mg, i.m., progesterone (n=10). In Experiment 1, the interval to new wave emergence for control, follicular ablation and 17β-oestradiol-treated groups was 4.9±0.7, 1.1±0.1 and 3.1±0.4 days, respectively (P<0.05). The degree of synchrony was 2.4±0.4, 0.2±0.1 and 0.8±0.2 days, respectively (P<0.05). In Experiment 2, the interval to new wave emergence for control, follicular ablation and 17β-oestradiol + progesterone-treated groups was 4.9±0.7, 1.2±0.2 and 3.3±0.3 days, respectively (P<0.05), and the degree of synchrony was 2.4±0.4, 0.2±0.1, and 0.8±0.2 days, respectively (P<0.05). The degree of synchrony did not differ between ablation and hormone treatment groups in either experiment, but was greater in treatment groups than in the untreated control phase. Both follicular ablation and hormone treatment shortened and decreased the variability in the interval to follicular wave emergence in bison, but wave emergence occurred earlier after follicular ablation.
authors.affiliation: Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, SK S7N5B4, Canada.
authors.forename: J Manuel
authors.initials: JM
authors.lastname: Palomino
authors.affiliation: Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, 3280 Hospital Drive NW, Calgary, AB T2N 4Z6, Canada.
authors.forename: Robert B
authors.initials: RB
authors.lastname: McCorkell
authors.affiliation: Department of Large Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, SK S7N5B4, Canada.
authors.forename: Murray R
authors.initials: MR
authors.lastname: Woodbury
authors.affiliation: Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, SK S7N5B4, Canada.
authors.forename: Gregg P
authors.initials: GP
authors.lastname: Adams
mesh_terms: D055011:Ablation Techniques / Q000662:veterinary*; D000818:Animals; D000858:Anovulation; D016164:Bison / Q000502:physiology*; D056727:Endangered Species; D004958:Estradiol / Q000494:pharmacology*; D004973:Estrus Synchronization / Q000187:drug effects*; D005260:Female; D006080:Ovarian Follicle / Q000187:drug effects* / Q000502:physiology / Q000601:surgery*; D010060:Ovulation / Q000187:drug effects*; D010062:Ovulation Induction / Q000662:veterinary*; D011374:Progesterone / Q000494:pharmacology*; D012621:Seasons; D013997:Time Factors
chemical_list: D011374:Progesterone; D004958:Estradiol