title: Effect of cow age on the in vitro developmental competence of oocytes obtained after FSH stimulation and coasting treatments.
abstract: The use of oocytes obtained from younger donors for IVF followed by embryo transfer represents an opportunity to accelerate genetic gain by reducing generation time. In this study, we investigated the relationship between donor age and the in vitro developmental competence of oocytes obtained from Holstein females (aged 5-18 months) after FSH stimulation and coasting. The follicle size patterns showed a significantly higher total number of small follicles (5-6 mm) from donors aged 5 to 10 months and a higher total number of medium-sized follicles (7-10 mm) in donors aged 6 to 7 months. Our analysis also revealed that the total number of follicles was significantly higher (P < 0.05) in donors aged 5 to 8 months and tended to be higher (P = 0.053) in nine-month-old donors. However, oocytes obtained from donors aged 5 to 10 months yielded fewer embryos reaching the morula and blastocyst stages. In summary, our results demonstrate that a higher number of oocytes can be obtained from younger animals but lower developmental competence negates this gain.
authors.affiliation: Centre de Recherche en Biologie de la Reproduction, Département des Sciences Animales, Faculté des sciences de l'agriculture et de l'alimentation, Université Laval, Québec, Canada.
authors.forename: David A
authors.initials: DA
authors.lastname: Landry
authors.affiliation: L'Alliance Boviteq Inc, Saint-Hyacinthe, Québec, Canada.
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Bellefleur
authors.affiliation: L'Alliance Boviteq Inc, Saint-Hyacinthe, Québec, Canada.
authors.forename: Rémi
authors.initials: R
authors.lastname: Labrecque
authors.affiliation: L'Alliance Boviteq Inc, Saint-Hyacinthe, Québec, Canada.
authors.forename: François-Xavier
authors.initials: FX
authors.lastname: Grand
authors.affiliation: L'Alliance Boviteq Inc, Saint-Hyacinthe, Québec, Canada.
authors.forename: Christian
authors.initials: C
authors.lastname: Vigneault
authors.affiliation: L'Alliance Boviteq Inc, Saint-Hyacinthe, Québec, Canada.
authors.forename: Patrick
authors.initials: P
authors.lastname: Blondin
authors.affiliation: Centre de Recherche en Biologie de la Reproduction, Département des Sciences Animales, Faculté des sciences de l'agriculture et de l'alimentation, Université Laval, Québec, Canada. Electronic address: marc-andre.sirard@fsaa.ulaval.ca.
authors.forename: Marc-André
authors.initials: MA
authors.lastname: Sirard
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D002417:Cattle / Q000502:physiology*; D046149:Embryo Culture Techniques; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology*; D009865:Oocytes / Q000502:physiology*; D012189:Retrospective Studies
chemical_list: D005640:Follicle Stimulating Hormone
keywords: Bos taurus; Developmental competence; Follicle population; Oocyte donor age; Ovarian stimulation