to produce embryogenic callus and somatic embryos, tendril explants were collected and cultured in ms medium supplemented with various concentrations of hormones. after one month most of explants produced callus. the highest percent of embryogenic callus obtained in ms medium supplemented with 4.5 µm bap and 1µm 2,4-d. production of somatic embryos was depended on genotype and medium. yaghouti ...

The relationship of plasminogen activator (PA) production to cell stage, cell number and changes in overall diameter and zona pellucida thickness for bovine embryos developing in vitro was determined. Late morulae to blastocysts (n = 80) were collected nonsurgically from naturally mated, estrous-synchronized, superovulated crossbred beef cows. Embryos were cultured, one embryo per 25-microliter...

OBJECTIVE To evaluate how the ranking of IVF programs changes if high-order multiple pregnancies (HOMPs) are considered negative outcomes. DESIGN Retrospective analysis. SETTING The 2004 Society for Assisted Reproductive Technology Clinic Outcome Reporting System. PATIENT(S) Two hundred seven programs that performed >50 IVF cycles were analyzed, and only patients <or=35 years of age were ...

BACKGROUND Multiple births are associated with serious adverse infant and maternal outcomes. The objective of this study was to assess the multiple-birth risk (MBR) associated with IVF and determine whether the risk is impacted by stage of embryo development at transfer. METHODS A population-based sample of 50 819 IVF transfers utilizing day 3 or day 5 embryos performed in the USA in 2001 on ...

To optimize success rates of IVF, selection of the most viable embryo(s) for transfer has always been essential, as embryos that are cryopreserved are thought to have a reduced chance of implanting after thawing. Recent developments challenge this concept. Evidence is accumulating that all embryos can now be cryopreserved and transferred in subsequent cycles without impairing pregnancy rates or...

introduction: this study was designed to compare the effects of three vitrification procedures [conventional (c), open pulled straw (ops) and closed pulled straw (cps)] on morphological survival of two-cell mouse embryos and their subsequent development to hatched blastocysts. material and methods: two-cell mouse embryos were divided into four groups, control (194), ops (150), cps (155) and c (...

During spring, summer and winter seasons, Sistani donor cows, with normal reproductive status, were superovulated and embryos were recovered non-surgically on day 7. Grade A blastocyst embryos were either transferred fresh (spring) or frozen (summer and winter). Recovered embryos during summer and winter were exposed to glycerol and frozen using conventional method. During spring season, recipi...

To optimize success rates of IVF, selection of the most viable embryo(s) for transfer has always been essential, as embryos that are cryopreserved are thought to have a reduced chance of implanting after thawing. Recent developments challenge this concept. Evidence is accumulating that all embryos can now be cryopreserved and transferred in subsequent cycles without impairing pregnancy rates or...