In vitro assessment of embryo viability

Abstract

With the advent and increasing adoption of methodologies to manipulate the mammalian embryo in vitro, increased emphasis is being placed on the predictive assessment of embryo viability in vitro. The development of viability assays that objectively measure the developmental competence of individual embryos will augment and accelerate selective genetic improvement of livestock through the use of embryo transfer, cryopreservation, genetic manipulation and in vitro embryo production procedures. The rationale, objective requirements and development of current methodologies used to assess embryo viability in vitro are reviewed. The specific advantages/limitations and application of several methodologies are discussed, and a novel multi-parametric evaluation strategy is proposed. The further development of novel or existing viability tests, that are rapid, non-perturbing, objective and of high resolution, will enhance success of in vitro embryo manipulation procedures, will improve the success of bovine embryo transfer programs, and will have potential application in exotic zoo/wildlife species and in human infertility programs.