Blood serum progesterone (P4) levels in donor cows and heifers at donor selection, superovulation, insemination and embryo recovery were investigated. Significant differences in P4 levels in the investigated donors during superovulatory oestrus insemination were observed. The cows with low levels of P4 at insemination (5.8 ± 1.7 nmol/l) showed a better yield and quality of embryos (P<0.01) comp...

Thirty nonlactating Holstein cows were superovulated to determine the effect of artificial insemination time on fertilization status and embryo quality. During the luteal phase of the estrous cycle, cows were administered 38 mg FSH-P in a 4-d descending dose regimen. Luteolysis was induced with two injections of prostaglandin on the last day of FSH-P treatment. All cows were continuously monito...

This review evaluates the quality of bovine embryos developed from in vitro-matured (IVM) and -fertilized (IVF) oocytes cultured in either serum-free or serum-containing media. Bovine embryos cultured in serum-supplemented medium contain numerous cytoplasmic lipid droplets and immature mitochondria compared to those cultured in serum-free medium. The accumulation of cytoplasmic lipids in embryo...

the society for assisted reproductive technology (sart) method of embryo grading is unique, simple, and widely practiced, and its use has been mandatory for sart membership programs since 2010. developed by sart in 2006, the current embryo grading system categories, “good, fair, and poor,” are limited because they do not describe the best 1-2 embryos in the interest of keeping pace with the shi...

background: melatonin, a reactive oxygen species (ros) scavenger and an antioxidant, has been shown that can inhibit apoptosis. administration of melatonin may improve embryo development in assisted reproductive technology (art). objective: the aim of this study was to evaluate the role of melatonin in inhibition of spontaneous and induced apoptosis by tumor necrosis factor alph (tnf-α) and act...

In recent decades, the adverse effects of global warming on all living beings have been unanimously recognized across world. A high environmental temperature that increases respiration and rectal cattle is called heat stress (HS), it can affect both male female reproductive functions. For successful reproduction fertilization, mature healthy oocytes are crucial; however, HS reduces developmenta...