title: Embryo development in dairy cattle.
abstract: During the past 50 years, the fertility of high-producing lactating dairy cows has decreased, associated with intensive selection for increased milk production. The physiological and metabolic changes associated with high milk production, including decreased (glucose, insulin, IGF-I) or increased (nonesterified fatty acids, ketone bodies) concentrations of circulating metabolites during nutrient partitioning associated with negative energy balance as well as uterine and nonuterine diseases have been linked with poor reproductive efficiency. Fertilization is typically above 80% and does not seem to be the principal factor responsible for the low fertility in dairy cows. However, early embryonic development is compromised in high-producing dairy cows, as observed by most embryonic losses occurring during the first 2 weeks after fertilization and may be linked to compromised oocyte quality due to a poor follicular microenvironment, suboptimal reproductive tract environment for the embryo, and/or inadequate maternal-embryonic communication. These and other factors related to embryo development will be discussed.
authors.affiliation: School of Agriculture and Food Science, University College Dublin, Dublin, Ireland. Electronic address: pat.lonergan@ucd.ie.
authors.forename: Pat
authors.initials: P
authors.lastname: Lonergan
authors.affiliation: School of Agriculture and Food Science, University College Dublin, Dublin, Ireland.
authors.forename: Trudee
authors.initials: T
authors.lastname: Fair
authors.affiliation: Division of Reproduction and Early Development, Leeds Institute of Cardiovascular and Molecular Medicine, School of Medicine, University of Leeds, Leeds, United Kingdom.
authors.forename: Niamh
authors.initials: N
authors.lastname: Forde
authors.affiliation: Departamento de Reproducción Animal Conservación de Recursos Zoogenéticos, INIA, Madrid, Spain.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Rizos
mesh_terms: D000818:Animals; D002417:Cattle / Q000196:embryology*; D004622:Embryo, Mammalian / Q000502:physiology*; D047108:Embryonic Development / Q000502:physiology*; D005260:Female; D011247:Pregnancy
keywords: Cattle; Conceptus; Embryo gene expression; Embryo mortality