Induction of superovulation and recovery of fertilized oocytes in prepubertal miniature pigs after treatment with PG600.

摘要

The purpose of this study was to examine whether superovulation could be induced by hormonal treatment with PG600 (400 IU equine chorionic gonadotropin and 200 IU HCG) at the prepubertal stage in miniature pigs. In experiment 1, 14 prepubertal miniature pigs received 1, 1/2 or 1/4 vial of PG600, i.m. on day 0 (the first day of treatment). Presentation of oestrus was monitored thereafter. On days 10-13 (6-8 days after oestrus), the number of corpora lutea (CL) and residual follicles was counted by an exploratory laparotomy. Injection of 1/2 vial of PG600 effectively induced oestrus and ovulation in the pigs. In experiment 2, 15 prepubertal miniature pigs that received 1/2 vial of PG600 were artificially inseminated into the uterus by an exploratorylaparotomy at 100-104 h after PG600 injection. Oocytes were recovered from the oviducts at 121-145 h after PG600 administration. The oocyte recovery rate was 66% (15 oocytes/pig), and 84% of these were at the 1-cell stage. In experiment 3, 5 prepubertalminiature pigs that received 1/2 vial of PG600, followed by 100 IU HCG 70 h later, were artificially inseminated into the uterus. Oocytes were recovered synchronously at 120-122 h after PG600 treatment. The recovery rate was 80% (17 oocytes/pig) and 90%of the oocytes recovered were at the 1-cell stage. It is concluded that superovulation of prepubertal miniature pigs can be induced by 1/2 vial of PG600 injection, and by the combined treatment with PG600 and HCG injection, the fertilized ova can be synchronously recovered at around 120 h after PG600 injection. This procedure may provide a useful system for biomedical research using the miniature pigs, especially for producing transgenic animals for use in human disease models.