Analysis of physical traits, clinical parameters, and energy metabolism of in vivo- and in vitro-derived Flemish newborn calves during the first day of life.

Studies investigating physiological deviations from normality in newborn calves derived from in vitro fertilization procedures remain important for the understanding of factors that reduce calf survival after birth. The aim of this study was to investigate parameters affecting health and welfare of newborn Flemish calves derived from in vitro embryo production (IVP) in the first hours of life in comparison to in vivo-derived calves. Physical traits of newborn calves and fetal membranes (FM) were recorded soon after birth.

Expression profile of key genes involved in DNA repair mechanisms in bovine cumulus cells cultured with bovine serum albumin or fetal calf serum.

Cumulus cells from cumulus-oocyte complexes (COC) matured in vitro in serum-free medium show high incidence of apoptosis and DNA double-strand breaks (DSB). This study aimed to characterize the transcript expression profile of selected genes involved in DNA repair mechanisms in bovine cumulus cells cultured with bovine serum albumin (BSA) or fetal calf serum (FCS). Briefly, bovine cumulus-oocyte complexes were in vitro matured with either, 0.

Porcine IVF embryo development and estrogen receptors are influenced by the concentration of percoll gradients during sperm selection.

This study aimed to evaluate the effect of three different concentrations of discontinuous gradients of percoll (90/45, 80/40, and 70/35) in the outcome of porcine in vitro fertilization (IVF) and its influence on further embryo development and quality. Embryo viability was assessed by the expression of estrogen receptors (E R) and cleaved caspase-3 (CC3). The highest percoll concentration (90/45) resulted in the lowest embryo production (24.

Production of bovine hand-made cloned embryos by zygote-oocyte cytoplasmic hemi-complementation.

The aim of this study was to evaluate the effect of the cytoplast type and activation process on development of cloned embryos. Bovine oocytes (MII) or zygotes at the one-cell stage (IVF) were manually bisected and segregated in MII or IVF hemi-cytoplasts or hemi-karyoplasts. Adult skin cells from a bovine female were used as nucleus donors (SC).

Developmental potential of bovine hand-made clone embryos reconstructed by aggregation or fusion with distinct cytoplasmic volumes.

Animal cloning has been associated with developmental abnormalities, with the level of heteroplasmy caused by the procedure being one of its potential limiting factors. The aim of this study was to determine the effect of the fusion of hemicytoplasts or aggregation of hemiembryos, varying the final cytoplasmic volume, on development and cell density of embryos produced by hand-made cloning (HMC), parthenogenesis or by in vitro fertilization (IVF). One or two enucleated hemicytoplasts were paired and fused with one skin somatic cell.