The role of fatty acids in oocyte and early embryo development

Growing evidence suggests that endogenous and exogenous fatty acids play diverse roles in developing mammalian oocytes and early embryos. In this review, we describe some of the regulatory roles of fatty acids in early development, in addition to their metabolic functions. We focus initially on the provision of individual fatty acids, and then discuss how these might affect metabolism, oxidative stress, membrane composition, cell signalling events and gene expression. We propose that ongoing research should focus on physiologically relevant ratios and combinations of fatty acids, rather than isolated individual fatty acids, as their combined roles are both subtle and complex. Changing the ratio of specific fatty acids in the diet of animal models, and in vitro culture medium can cause significant dysregulation of cellular processes and development, an issue that extends to human fertility

Comparison of different fertilisation media for an in vitro maturation-fertilisation-culture system using flow-cytometrically sorted X chromosome-bearing spermatozoa for bovine embryo production

High demand exists among commercial cattle producers for in vitro-derived bovine embryos fertilised with female sex-sorted spermatozoa from high-value breeding stock. The aim of this study was to evaluate three fertilisation media, namely M199, synthetic oviductal fluid (SOF) and Tyrode's albumin-lactate-pyruvate (TALP), on IVF performance using female sex-sorted spermatozoa. In all, 1143, 1220 and 1041 cumulus-oocyte complexes were fertilised in M199, SOF and TALP, respectively. There were significant differences among fertilisation media (P<0.05) in cleavage rate (M199≤57%, SOF≤71% and TALP≤72%), blastocyst formation (M199≤9%, SOF≤20% and TALP≤19%), proportion of Grade 1 blastocysts (M199≤15%, SOF≤52% and TALP≤51%), proportion of Grade 3 blastocysts (M199≤58%, SOF≤21% and TALP≤20%) and hatching rates (M199≤29%, SOF≤60% and TALP≤65%). The inner cell mass (ICM) and trophectoderm (TE) cells of Day 7 blastocysts were also affected by the fertilisation medium. Embryos derived from SOF and TALP fertilisation media had higher numbers of ICM, TE and total cells than those fertilised in M199. In conclusion, fertilisation media affected cleavage rate, as well as subsequent embryo development, quality and hatching ability. SOF and TALP fertilisation media produced significantly more embryos of higher quality than M199.Fil: Ferré, Luis Bernardo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; ArgentinaFil: Bogliotti, Yanina. University of California; Estados UnidosFil: Chitwood, James L.. University of California; Estados UnidosFil: Fresno Rodríguez, Cristóbal. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Catolica de Córdoba. Facultad de Ingeniería; ArgentinaFil: Ortega, Hugo Hector. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; ArgentinaFil: Kjelland, Michael E.. Conservation, Genetics and Biotech; Estados UnidosFil: ROSS, Pablo Juan. University of California; Estados Unido