title: Induction of estrus in pubertal miniature gilts.
abstract: Genetic engineering of miniature pigs has facilitated the development of numerous biomedical applications, such as xenotransplantation and animal models for human diseases. Manipulation of the estrus is one of the essential techniques for the generation of transgenic offspring. The purpose of the present study was to establish a useful method for induction of the estrus in miniature gilts. A total of 38 pubertal miniature gilts derived from 4 different strains were treated with exogenous gonadotropins. Estrus and ovulatory response were examined after treatment with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG) as 200 IU PMSG and 100 IU hCG, 300 IU PMSG and 150 IU hCG, or 1,500 IU PMSG only, followed by 100, 150 or 750 IU hCG 72 h later, respectively. The optimal protocol was determined to be the combination treatment of 200 IU PMSG and 100 IU hCG followed by 100 IU hCG. The administration of 200 IU PMSG and 100 IU hCG was effective in inducing estrus regardless of the strain, although there was a strain difference in the ovulatory response. These results indicate that treatment with a low-dose combination of PMSG and hCG provides one of the simplest methods for induction of estrus and ovulation in pubertal miniature pigs.
authors.affiliation: Laboratory of Animal Reproduction, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidouri-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan. wakai@bios.tohoku.ac.jp
authors.forename: Takuya
authors.initials: T
authors.lastname: Wakai
authors.forename: Hozumi
authors.initials: H
authors.lastname: Tanaka
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Yamanaka
authors.forename: Satoshi
authors.initials: S
authors.lastname: Sugimura
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sasada
authors.forename: Manabu
authors.initials: M
authors.lastname: Kawahara
authors.forename: Eiji
authors.initials: E
authors.lastname: Kobayashi
authors.forename: Eimei
authors.initials: E
authors.lastname: Sato
mesh_terms: D000818:Animals; D004971:Estrus / Q000187:drug effects* / Q000502:physiology; D005260:Female; D006062:Gonadotropins / Q000494:pharmacology*; D010062:Ovulation Induction / Q000379:methods / Q000662:veterinary*; D013552:Swine; D013556:Swine, Miniature / Q000502:physiology*
chemical_list: D006062:Gonadotropins