title: Effects of pregnant mare's serum gonadotropin treatment on follicular populations and ovulation rates in prepuberal gilts with two morphologically different ovarian types.
abstract: Two experiments were conducted to determine the effects of pregnant mare's serum gonadotropin (PMSG) on follicular populations and ovulation rates in prepuberal gilts with grape-type (GT) and honeycomb-type (HT) ovaries. The follicular populations were determined at 170 d of age (d 0) and 19 d after PMSG (d 19). In Exp. 1, the mean number of macroscopic follicles of Classes 2 and 3 was greater (P less than .05) in GT (n = 11) than in HT (n = 32) ovaries at d 0, whereas the mean number of those of Class 1 was greater (P less than .05) in HT ovaries. At d 19, no difference was observed between the two ovarian types for any class of follicles. The PMSG-induced ovulation rates were comparable between the two ovarian types (8.3 vs 7.9, GT vs HT, respectively; P greater than .10). In Exp. 2, the microscopic follicular populations were determined on right and left ovaries removed, respectively, on d 0 and 19. At d 0, GT ovaries (n = 5) contained a greater number of Class 5 nonatretic (P less than .01) and atretic (P less than .02) follicles than did HT ovaries (n = 5), whereas at d 19 the mean number was not statistically different between the two ovarian types (P greater than .10). In contrast, gilts with HT ovaries contained a greater (P less than .01) number of Class 4 atretic follicles than gilts with GT ovaries at d 0, whereas at d 19 the mean number was not statistically different between the two ovarian types (P greater than .10).(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Département de Zootechnie, Université Laval, Québec, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Bolamba
authors.forename: P
authors.initials: P
authors.lastname: Matton
authors.forename: R
authors.initials: R
authors.lastname: Estrada
authors.forename: J J
authors.initials: JJ
authors.lastname: Dufour
mesh_terms: D000818:Animals; D005260:Female; D005496:Follicular Atresia / Q000187:drug effects; D006064:Gonadotropins, Equine / Q000494:pharmacology*; D006080:Ovarian Follicle / Q000187:drug effects*; D010053:Ovary / Q000033:anatomy & histology; D010060:Ovulation / Q000187:drug effects*; D010062:Ovulation Induction / Q000662:veterinary*; D013552:Swine / Q000502:physiology*
chemical_list: D006064:Gonadotropins, Equine