ATP content and maturational/developmental ability of bovine oocytes with various cytoplasmic morphologies

Abstract

SummaryWe examined the relationship among morphological appearance (six groups) of bovine oocytes, ATP content and maturational/developmental ability. Oocytes with a brown ooplasm (with or without a dark region) had intermediate levels of ATP at the germinal vesicle (GV) stage and showed higher rates of first polar body (PB) extrusion than the other groups. Oocytes with a low level of ATP (oocytes with a pale ooplasm without dark clusters) and oocytes with a high level of ATP (oocytes with a black ooplasm) showed lower rates of PB extrusion. During in vitro maturation, ATP levels in oocytes decreased at around GV breakdown and increased toward metaphase II (MII). MII oocytes having a brown ooplasm with a dark region, which had good developmental capacity, had a relatively high level of ATP. MII oocytes with a brown or pale ooplasm without dark clusters, which had poor developmental capacity, had low ATP levels. MII oocytes with a black ooplasm, which had poor developmental capacity, had an unusually high level of ATP. These results suggest that the morphological appearance of bovine oocytes is closely related to their ATP levels and that cytoplasmic morphology will give an advantage for the selection of oocytes with a high maturational and developmental ability.

Effects of in vitro growth culture duration and prematuration culture on maturational and developmental competences of bovine oocytes derived from early antral follicles

“…Oocytes were denuded from cumulus cells by vortexing and stained with 1% 16 aceto-orcein as described elsewhere [21]. Nuclear statuses were classified as germinal 17 …”

Effect of duration of in vitro maturation on nuclear maturation and fertilizability of feline oocytes

“…They were then fixed with a mixture of ethanol: acetic acid (3:1), stained with 1% aceto-orcein solution, and nuclear status and the presence of pronuclei were evaluated using a phase-contrast microscope, as described previously [22,23]. Briefly, the presence of two pronuclei was regarded as normal fertilization, whereas three or more pronuclei and/or enlarged sperm heads within an oocyte was judged as polyspermy.…”

Efecto De La Aplicación De Gonadotropinas Recombinantes Humanas Sobre La Producción Y Calidad De Ovocitos Y Embriones en Coneja

“…In order to determine the effect of these superovulation treatments on oocyte quality, ATP amount in recovered oocytes was determined. It has been described previously that mitochondrial dysfunction and ATP content may be related to developmental competence in oocytes and embryos (Van Blerkom et al, 1995;Thouas et al, 2004;Nagano et al, 2006). Although difference in ATP level was non significant when compared to control group, significant differences in ATP content were found between different superovulatory treatments.…”

“…Otherwise, how ATP levels are affected during oocyte maturation seems to be still unclear and seems to be very specie-specific; it has been observed that in vitro maturation and maturation conditions may impact on mitochondrial activity in rabbits , mouse (Combelles y Albertini, 2003), cows Nagano et al, 2006), gilts (Brevini et al, 2005) or cats (Freistedt et al, 2001). …”