Ram spermatozoa are most susceptible to damage during freezing between the temperatures of -10 degrees C and -25 degrees C. The objectives of the present study were to examine how freezing rate through this critical temperature zone affected the fertility of spermatozoa as assessed in vivo and in vitro. Semen from six adult rams was frozen at two different rates ("fast": 5 degrees C/min from +5...

OBJECTIVE The decision to use in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), or split insemination (IVF-ICSI) in the first cycle is based on the number of motile sperm. Hence, total fertilization failure (TFF) often occurs during IVF cycles, despite normozoospermia. To investigate whether the cumulative motile swim-up spermatozoa percentage at 22 hours post-insemination ...

Objective. To investigate the association between assisted conceptions and preeclampsia (PEC), including assessment of severity of disease. Methods. In a prospective case control study, cases were selected from women with preeclampsia and controls from women without preeclampsia. Exposure was defined as assisted conception with intrauterine insemination or in vitro fertilization (IUI or IVF). W...

Exposure of in vitro cultured human embryos to microvibrations can improve embryo development, but music as a source of mechanical vibrations has not yet been explored. To determine the effect of the exposure to music during in vitro culture, 967 oocytes (114 patients) were analyzed. Before insemination, oocytes from each patient were randomly assigned to two groups: embryo culture exposed to m...

The objective was to determine the effect of sequence of insemination after simultaneous thawing of multiple 0.5 mL semen straws on conception rate in suckled multiparous Nelore cows. The effect of this thawing procedure on in vitro sperm characteristics was also evaluated. All cows (N = 944) received the same timed AI protocol. Ten straws (0.5 mL) of frozen semen from the same batch were simul...

PURPOSE A prospective study was planned to determine the relationship between post swim-up acrosome index (AI) evaluation and fertilization outcomes in an in vitro fertilization (IVF) program. MATERIALS AND METHODS Infertile couples who have applied to IVF were admitted into this study when the male partner's sperm concentration was > 20 x 10(6)/mL and motility > 30%. Pre- and post swim-up se...

A modified Tris-buffered medium (mTBM) has been widely used as an insemination medium for porcine in vitro fertilization (IVF). We examined whether mTBM could be used for bovine IVF. Bovine cumulus-oocyte complexes (COCs) were cultured in a serum-free medium containing 30 ng/ml EGF for 22 h. After culture, COCs were inseminated with spermatozoa for 12 h in mTBM containing 5 mM caffeine and 10 g...

background: vitrification has proven to be more effective than slow freezing methods to cryopreserve mammalian oocytes. the objectives of this study were to evaluate the effects of vitrification on immature and in vitro matured, denuded and cumulus compact goat oocytes and their subsequent fertilization. methods: oocytes were either cryopreserved as immature cumulus compact (imcc) (n=98 exp 1; ...

background: it is important to protect oocytes and embryos from oxidative stress in the culture medium. melatonin has been shown to be a direct free radical scavenger. objective: effect of melatonin during in vitro oocyte maturation, fertilization and embryo development of mouse oocytes was evaluated. materials and methods: oocytes from supper-ovulated mouse were divided to two groups: cumulus ...

The cortical reaction induces changes at the egg's Zona pellucida (ZP), perivitelline space and/or oolemma level, blocking polyspermic fertilization. We studied the timing of sperm penetration and cortical reaction in pig oocytes matured under different conditions and inseminated with different boars. Immature (germinal vesicle stage) and in vitro matured (IVM) (metaphase II stage) oocytes were...