Chromosome analysis of horse oocytes  cultured in vitro

King, W.A.; Desjardins, M.; Xu, Kangpu; Bousquet, D.

doi:10.1051/gse:19900201

Cited by 4 publications

(4 citation statements)

References 9 publications

(13 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Irrespective of the staining technique, in the present study the percentage of oocytes characterized as GV stage at the time of collection differs from those reported in the literature [King et al, 1990;Okolski et al, 1991;Bézard and Palmer, 1992;Del Campo et al, 1992;Hinrichs et al, 1993a;Willis et al, 1994;Torner and Alm, 1995;Brück et al, 1996]. In addition to differences in the staining technique and the morphological characterization of the meiotic stages, the origin of the oocyte (i.e.…”

Section: Discussioncontrasting

confidence: 55%

Comparative Evaluation of Nuclear Morphology of Equine Oocytes Aspirated in vivo and Stained with Hoechst and Orcein

Bézard

Bøgh

Duchamp

et al. 2002

Cells Tissues Organs

View full text Add to dashboard Cite

Nuclear maturation of equine oocytes was assessed immediately after in vivo collection. A double-staining technique (Hoechst and orcein) was used on the same oocytes to visualize nuclear morphology, i.e. to evaluate the chromatin configurations of each oocyte after Hoechst in relation to the nuclear morphology after orcein staining. The proportion of oocytes evaluated as germinal vesicle stages was significantly (p < 0.02) lower after Hoechst (14.5%) than after orcein staining (29.0%), while the incidence of the so-called dense chromatin stage was assessed to be higher (p < 0.05) after Hoechst than after orcein staining (14.5 vs. 6.5%). There was no difference between Hoechst and orcein staining in the incidence of diakinesis and germinal vesicle breakdown stages, respectively (44.9 vs. 42.0%), and the same applied for metaphase I (11.6 vs. 8.0%), metaphase II (7.2 vs. 8.0%) and degenerated stages (7.2 vs. 6.5%). It was concluded that the interpretation of the meiotic stages may differ between Hoechst and orcein staining and in a large proportion of equine oocytes the nuclear border may not be visualized on orcein staining.

show abstract

Section: Discussioncontrasting

confidence: 55%

Comparative Evaluation of Nuclear Morphology of Equine Oocytes Aspirated in vivo and Stained with Hoechst and Orcein

Bézard

Bøgh

Duchamp

et al. 2002

Cells Tissues Organs

View full text Add to dashboard Cite

show abstract

“…While oocytes of other species also show condensation of chromatin around the nucleolus, associated with acquisition of meiotic competence (Daguet, 1980; Gougeon and Testart, 1986; Mattson and Albertini, 1990), the condensation seen in horse oocytes is more extreme, forming one dense mass around an apparent nucleolus, and appears to be similar to that reported in the human (Gougeon and Testart, 1986; Parfenov et al, 1989). The CC configuration has led to confusion as some reports state that at the time of collection from the follicle, the majority of Ex oocytes are in diakinesis (King et al, 1990), resumption of meiosis (Torner and Alm, 1995), or MI (Zhang et al, 1989). However, centrifugation of oocytes to allow visualization of the nuclear membrane indicates that oocytes having the CC configuration (Fig.…”

Section: Nuclear Maturationmentioning

confidence: 99%

The equine oocyte: Factors affecting meiotic and developmental competence

Hinrichs

2010

Molecular Reproduction Devel

View full text Add to dashboard Cite

SUMMARYThere is currently much interest in assisted reproduction techniques in the horse, however, many aspects of oocyte maturation, fertilization, and embryo development in the horse differ from those in other species. Because of the close attachment of the equine oocyte to the follicle wall, scraping of the follicle is the most effective method for oocyte recovery. A notable feature of equine oocytes is that those with expanded cumuli (Ex oocytes), which originate from atretic follicles, have higher meiotic competence (ability to mature to metaphase II in vitro) than do oocytes with compact cumuli (Cp oocytes). Cp oocytes originate in viable follicles but are largely juvenile. Recovery and culture of equine oocytes immediately after slaughter yields a higher maturation rate than that obtained from oocytes after ovary storage; this is related to damage to chromatin in Cp oocytes during storage. In contrast, developmental competence (rate of blastocyst development in vitro) is higher in oocytes recovered from the ovary after a delay. The optimum duration of maturation varies based on cumulus morphology and time of recovery from the ovary, but there is no difference in developmental competence between Ex and Cp oocytes. Because standard in vitro fertilization is not repeatable in the horse, oocyte transfer (surgical transfer of oocytes to the oviducts of inseminated mares) has been developed to allow fertilization of isolated oocytes. Fertilization in vitro may be achieved using intracytoplasmic sperm injection; culture of injected oocytes in a medium with high glucose can yield over 30% blastocyst development.Mol. Reprod. Dev. 77: 651-661,

show abstract

“…The time required for maturation of equine oocytes has been reported by many investigators but the results varied among their studies (Fulka and Ok6lski, 1981;King et al, 1990;Willis et al,1991Willis et al, a,b, 1994Hinrichs et al, 1993;Aim and Tomer, 1994;Del Campo et al, 1995).…”

mentioning

confidence: 99%

“…Nevertheless, it is known that the maturation time in the horse is longer than in cattle, sheep and goats, which is about 24 h (Gordon, 1994 (1988) and modification for horse oocytes by King et al (1990) (fig 1). (1992) and Sronina and Ok6lski (1993): 59 and 65%, respectively.…”

mentioning

confidence: 99%