Comparative morphometry of precompacted bovine embryos produced in vivo or in vitro after parthenogenetic activation and intracytoplasmic sperm injection (ICSI): ultrastructural analysis

Abstract

Early bovine precompacted embryos (1 to 8 blastomeres) were analysed by electron microscopy. The volume density of cellular components was determined by morphometric analysis to quantify the ultrastructure of early bovine embryos produced either in vivo or in vitro both after fertilisation by intracytoplasmic sperm injection (ICSI) or from electrically stimulated oocytes (AC/DC). In normal embryos obtained in vivo (control), most of the cellular volume was occupied by cytoplasm (82.93%). The relative volume of lipids, vacuoles, mitochondria, Golgi apparatus and inclusion bodies was minimal. In the group of embryos after parthenogenetic activation (AC/DC) a relatively high proportion of the volume was occupied by vacuoles and lipids (18.68% vs 14.33%). Early ICSI-derived embryos contained the lowest relative volume of cytoplasm (58.33%) compared with the control embryos (in vivo) and parthenogenetically AC/DC-activated embryos and a higher volume was occupied by lipids (13.25%) and vacuoles (12.92%). It is concluded that in vitro produced embryos have a significantly altered ultrastructure, indicating extensive cellular damage.

Present Status and Prospects for Bovine Intracytoplasmic Sperm Injection with In Vitro-Matured Oocytes and Frozen Semen

“…These methods also increase the subsequent maturation rate and developmental competence of the oocytes. However, IVM oocytes are more easily damaged by in vitro manipulation than in vivo-matured oocytes [16,17]. Insufficient in vitro maturation conditions lead to a decrease in inositol 1,4,5-trisphosphate (IP3) and glutathione stored via cumulus cells such that a possibility exists that this adversely affects oocyte activation and male pronucleus formation [12,18].…”

Survival and ultrastructure of gene-microinjected rabbit embryos after vitrification

“…Previously reported ultrastructural data on early-stage embryos from sheep and cattle have been based on subjective evaluations (Gardner et al, 1994;Shamsuddin et al, 1992). Morphometric analysis represents a more objective method of assessing differences in cellular ultrastructure (Crosier et al, 2000;Pivko et al, 2003) that may occur in embryos as a result of different interventions.…”

Obtención de embriones de ovino por transferencia nuclear a partir de Fibroblastos de piel y ovocitos maduros in vitro con resveratrol

“…Aunque un análisis morfológico ha mostrado ser un buen parámetro para evaluar la calidad de los embriones desarrollados in vitro, un análisis morfométrico representa un método más objetivo para evaluar las diferentes estructuras de la célula (Pivko et al, 2003). En este caso se han utilizado tinciones intracelulares como la bisbenzimida y el yoduro de propidio (Hosseini et al 2007).…”