Developmental competence of mouse embryos following zona drilling using a non-contact holmium:yttrium scandian gallium garnet (Ho:YSGG) laser system.

The purpose of this study was to assess the efficacy of the holmium:yttrium scandian gallium garnet (Ho:YSGG) laser, operating in a pipette-free, non-contact mode, to assist hatching and sustain normal embryonic development. Two-cell mouse embryos were recovered and assigned to laser-assisted hatching (LAH) treatment or control human tubal fluid (HTF) culture with or without serum (HTF-s, HTF-o) or with late serum supplementation (HTF-o/s). The basic experimental apparatus for LAH consisted of a stationary 2.

Physiological characterization of blastocyst hatching mechanisms by use of a mouse antihatching model.

Objectives: To use the protein-free medium blastocyst antihatching model to characterize physiological events that mediate hatching.

Design: In a series of four prospective experiments, our aims were to [1] test the efficacy of the antihatching model and assisted hatching; [2] exam the influence of initial in vivo developmental stage and late serum supplementation on hatching inhibition; [3] discount the role of zona hardness and physical expansion directly affecting hatching; and [4] provide evidence that the trophectoderm is directly responsible for secreting a zona lysin.

Setting: University-based research laboratory.

Relationship of morphology and follicular fluid environment of bovine oocytes to their developmental potential in vitro.

Morphology of bovine cumulus oocyte complexes (BCOC) and follicular fluid parameters were examined as potential criteria for selecting in vitro developmentally competent oocytes. Immature BCOC, from antral follicles, exhibiting similar morphological characteristics were grouped and the blastocyst development for oocytes in each group was examined. In a second experiment, follicles were individually aspirated to recover BCOC with their associated follicular fluid.