title: Efficacy of porcine gonadotropins for repeated stimulation of ovarian activity for oocyte retrieval and in vitro embryo production and cryopreservation in Siberian tigers (Panthera tigris altaica).
abstract: A comparison of the amino acid sequences demonstrated that Siberian tiger gonadotropins are more homologous with those of porcine than any other commercially available preparation. The present study measured the efficacy of repeated ovarian stimulation with purified porcine gonadotropins on the follicular, hormonal, and immunogenic responses in Siberian tigers as well as on the ability of oocytes retrieved by laparoscopic follicular aspiration to fertilize and cleave in vitro. Controlled rate and vitrification cryopreservation methods were also compared for their ability to support ongoing cleavage following thawing of presumptive 2- to 4-cell tiger embryos generated in vitro. Vitrification supported continued embryonic cleavage in vitro while controlled rate freezing did not. Stereological microscopy indicated an excellent ovarian response with the recovery of quality cumulus-oocyte complexes that apparently fertilized and cleaved in vitro. However, ultrastructural and physiological examination revealed abnormal and unnatural responses such as the failure of some cumulus-oocyte complexes to reach maturity and progestagen levels to approach normalcy. At the same time, analyses of blood for antibodies failed to detect an immune reaction to these foreign gonadotropins in an assay that tested positive for the chorionic gonadotropin-stimulated domestic cat. Together, these observations suggest that porcine gonadotropins may be effective for the ovarian stimulation of tigers but that some modifications to administration protocols are needed to produce a more natural response.
authors.affiliation: Center for Conservation and Research, Henry Doorly Zoo, Omaha, Nebraska 68107, USA.
authors.forename: Elizabeth G
authors.initials: EG
authors.lastname: Crichton
authors.forename: Elliott
authors.initials: E
authors.lastname: Bedows
authors.forename: Amanda K
authors.initials: AK
authors.lastname: Miller-Lindholm
authors.forename: David M
authors.initials: DM
authors.lastname: Baldwin
authors.forename: Douglas L
authors.initials: DL
authors.lastname: Armstrong
authors.forename: Laura H
authors.initials: LH
authors.lastname: Graham
authors.forename: J Joe
authors.initials: JJ
authors.lastname: Ford
authors.forename: Jakob O
authors.initials: JO
authors.lastname: Gjorret
authors.forename: Poul
authors.initials: P
authors.lastname: Hyttel
authors.forename: C Earle
authors.initials: CE
authors.lastname: Pope
authors.forename: Gabor
authors.initials: G
authors.lastname: Vajta
authors.forename: Naida M
authors.initials: NM
authors.lastname: Loskutoff
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002335:Carnivora / Q000235:genetics; D015925:Cryopreservation / Q000379:methods / Q000662:veterinary; D004622:Embryo, Mammalian; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods / Q000662:veterinary; D005640:Follicle Stimulating Hormone / Q000008:administration & dosage* / Q000235:genetics; D007986:Luteinizing Hormone / Q000008:administration & dosage* / Q000235:genetics; D008969:Molecular Sequence Data; D010062:Ovulation Induction / Q000379:methods / Q000662:veterinary*; D012099:Reproductive Techniques / Q000662:veterinary*; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D034421:Sus scrofa
chemical_list: D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone