background: many studies reported that follicle size has an essential role in developmental potential of oocytes. also, the brilliant cresyl blue (bcb) test is one of the most important criteria in selection of more competent oocytes. objective: selection of developmentally competent bovine oocytes. materials and methods: a total of 1730 bovine cumulus oocyte complexes (cocs) were recovered fro...

the purpose of this study was to evaluate the use of glass capillary micropipette (gcm) as a vessel forvitrification of bovine oocytes. cumulus-oocyte complexes (cocs) were obtained from slaughter-house andwashed 5 to 6 times in the washing medium (tcm-199 + 20% fbs) and randomly assigned to treatment andcontrol group. in the first step of vitrification, cocs were exposed to first vitrification...

background: previous studies reported many discrepancies about the effects of corpus luteum (cl) and ovarian follicle size on the developmental competence of oocytes. objective: the aim of this study was to investigate the effects of cl and different size of follicle on the developmental potential of bovine oocytes. materials and methods: after ovarian classification based on presence or absenc...

introduction: superovulation produces complications in some patients, so invitro maturation of oocytes is used to decrease or eliminate these complications and improve ivf. moreover, ivm is used for different aspects of reproductive researches. slaughterhouse ovaries are the main source of oocytes for ivm and ivf studies. different media has been introduced and experimented for in vitro maturat...

background: addition of amino acids to the culture medium is beneficial for embryonic development in many species. objective: the objective of this study was to investigate the effects of amino acids on the in vitro maturation and embryonic development of the bovine oocyte. materials and methods: bovine ovaries were collected from a local abattoir and brought into laboratory. cumulus-oocyte com...

the aim of the present study was to find the effects of pre and post vitrification taxol treatment on bovineimmature cumulus oocyte complexes (cocs). bovine ovaries were collected from the local slaughterhousein a container with 30-37°c physiologic saline and supplemented with antibiotics. the grade a aspiratedcocs were assigned to 6 experimental groups; the 1st group was control (n=100) in whi...

Background: In vitro maturation is a good method to decrease cancer risk of superovulation by gonadotropin hormones. A paracrine effect of oocyte secretions on oocyte developmental competence is under investigation. Apart from oocyte maturation, ovulation in vivo requires a precise control of extracellular matrix modification. Cumulus cells secrete hyaluronan to form a muco-elastic extracellula...

Bovine oocytes cultured in control medium or in medium containing dibutyrylcyclic adenosine monophosphate (dbcAMP) or an inhibitor of cyclic nucleotide phosphodiesterase (3-isobutyl-1-methylxanthine, IBMX) undergo germinal vesicle breakdown (GVBD). On the other hand, mouse oocytes remain arrested at the germinal vesicle (GV) stage when dbcAMP or IBMX is present. When 1 bovine GV stage oocyte is...

BACKGROUND The enzyme hyaluronidase from bovine origin is commonly used for oocyte-cumulus cell removal in ICSI. A recombinant human hyaluronidase (rHuPH20) has been introduced as a quality-controlled and safe alternative. METHODS In order to validate its effectiveness, a non-inferiority trial was started on sibling cumulus-oocyte complexes (135 ICSI patients). Oocyte denudation involved enzy...

Cyclic nucleotides cAMP and cGMP are among the main molecules that control maturation of mammal oocytes. The in vitro simulated physiological oocyte (SPOM) method was used to model accumulation oocyte. In current study, we preincubated oocytes cows (not primed with FSH) modulators: N 6,2’-O-dibutyryladenosine 3’,5’-cyclomonophosphate (dbcAMP) 3-isobutyl-1-methylxanthine (IBMX). use SPOM increas...