title: Effect of time and dose of recombinant follicle stimulating hormone agonist on the superovulatory response of sheep.
abstract: The objective of this study was to determine the superovulatory potential of a single-chain analog of human FSH (Fcα) when administered to ewes either 3 days before, or coincident with, simulated luteolysis (pessary removal [PR]). A total of 40 animals were randomly assigned to receive Fcα at doses of 0.62, 1.25, or 2.5 IU/kg of body weight (bwt) 3 days before PR or 0.31, 0.62, 1.25, or 2.5 IU/kg of bwt at PR. Control ewes received protein without FSH activity. Blood samples were collected during the periovulatory period and ovarian tissue was collected 11 days after PR. Ovulation rate did not differ from the control group in ewes receiving the smallest doses of Fcα (0.31 and 0.62 IU/kg). However, a significant superovulatory response was noted in sheep receiving Fcα at doses of 1.25 and 2.5 IU/kg and this response was comparable in animals receiving the largest dose levels of Fcα at, or 3 days before, PR. The interval between PR and the LH surge was significantly extended and the LH surges were less synchronous in animals receiving Fcα at PR when compared with animals receiving the potent FSH agonist 3 days before PR. Taken together, these data indicate that the human single-chain gonadotropin with FSH activity promotes superovulation in ewe lambs in the breeding season. A single injection of the recombinant gonadotropin 3 days before luteolysis synchronizes the LH surge. The use of the single-chain analog of FSH in assisted reproduction for domestic animals is likely to be of practical significance as an alternative to conventional gonadotropins in superovulation protocols in livestock species.
authors.affiliation: Department of Animal Science, University of California, Davis, California, USA. Electronic address: heloisa.rutigliano@usu.edu.
authors.forename: Heloisa M
authors.initials: HM
authors.lastname: Rutigliano
authors.affiliation: Department of Animal Science, University of California, Davis, California, USA.
authors.forename: Betty M
authors.initials: BM
authors.lastname: Adams
authors.affiliation: Department of Developmental Biology, Washington University School of Medicine, Saint Louis, Missouri, USA; Department of Obstetrics and Gynecology, Washington University School of Medicine, Saint Louis, Missouri, USA.
authors.forename: Albina
authors.initials: A
authors.lastname: Jablonka-Shariff
authors.affiliation: Department of Developmental Biology, Washington University School of Medicine, Saint Louis, Missouri, USA; Department of Obstetrics and Gynecology, Washington University School of Medicine, Saint Louis, Missouri, USA.
authors.forename: Irving
authors.initials: I
authors.lastname: Boime
authors.affiliation: Department of Animal Science, University of California, Davis, California, USA.
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Adams
mesh_terms: D000818:Animals; D004973:Estrus Synchronization; D005640:Follicle Stimulating Hormone / Q000008:administration & dosage / Q000819:agonists / Q000031:analogs & derivatives / Q000494:pharmacology*; D010062:Ovulation Induction / Q000379:methods / Q000662:veterinary*; D012756:Sheep / Q000502:physiology*; D013480:Superovulation / Q000187:drug effects*; D013997:Time Factors
chemical_list: D005640:Follicle Stimulating Hormone
keywords: Assisted reproductive technologies; Gonadotropin; Multiple ovulation; Ovine; Single-chain gonadotropin