Consequences of bovine oocyte maturation, fertilization or early embryo development in vitro versus in vivo: Implications for blastocyst yield and blastocyst quality
- D. Rizos, F. Ward, P. Duffy, M. Boland, P. Lonergan
- BiologyMolecular Reproduction and Development
- 1 February 2002
The results indicate that the intrinsic quality of the oocyte is the main factor affecting blastocyst yields, while the conditions of embryo culture have a crucial role in determining Blastocyst quality.
Bovine Embryo Culture in the Presence or Absence of Serum: Implications for Blastocyst Development, Cryotolerance, and Messenger RNA Expression1
- D. Rizos, A. Gutiérrez-Adán, S. Pérez-Garnelo, J. de la Fuente, M. Boland, P. Lonergan
- BiologyBiology of Reproduction
It is shown that conditions of postfertilization culture, in particular, the presence of serum in the medium, can affect the speed of embryo development and the quality of the resulting blastocysts.
Analysis of Differential Messenger RNA Expression Between Bovine Blastocysts Produced in Different Culture Systems: Implications for Blastocyst Quality1
The study of 7 differentially expressed mRNAs known to be involved in developmental process in the embryo suggests roles for apoptosis, oxidative stress, gap junctions, and differentiation in the determination of embryo quality.
Effect of follicle size on bovine oocyte quality and developmental competence following maturation, fertilization, and culture in vitro
- P. Lonergan, P. Monaghan, D. Rizos, M. Boland, I. Gordon
- BiologyMolecular Reproduction and Development
- 1 January 1994
It was found that administration of six injections of pFSH beginning 3 days prior to slaughter resulted in a significant increase in the proportion of follicles >6 mm in diameter compared to that in nontreated controls and to animals that received only four injection groups.
Temporal Divergence in the Pattern of Messenger RNA Expression in Bovine Embryos Cultured from the Zygote to Blastocyst Stage In Vitro or In Vivo1
The results demonstrate that the relative abundance of the transcripts studied varies throughout the preimplantation period and is strongly influenced by the culture environment, and changes in transcript abundance in blastocyst stage embryos are in many cases a consequence of perturbed transcription earlier in development.
Sex determines the expression level of one third of the actively expressed genes in bovine blastocysts
- P. Bermejo-Álvarez, D. Rizos, D. Rath, P. Lonergan, A. Gutiérrez-Adán
- BiologyProceedings of the National Academy of Sciences
- 23 February 2010
Comparison of gene-expression patterns between male and female blastocysts by DNA microarray comparison suggested a higher global transcriptional level in females and a more active protein metabolism in males, and a gene homolog to an X-linked gene involved in network interactions during spliceosome assembly was found in the Y-Chr.
Progesterone and conceptus elongation in cattle: a direct effect on the embryo or an indirect effect via the endometrium?
Data provide clear evidence to support the hypothesis that P(4)-induced changes in the uterine environment are responsible for the advancement in conceptus elongation reported previously in cattle and that, interestingly, the embryo does not need to be present during the period of high P( 4) in order to exhibit advanced elongation.
Elevated Non-Esterified Fatty Acid Concentrations during Bovine Oocyte Maturation Compromise Early Embryo Physiology
Exposure of maturing oocytes to elevated NEFA concentrations has a negative impact on fertility not only through a reduction in oocyte developmental capacity but through compromised early embryo quality, viability and metabolism.
Oocyte and embryo quality: effect of origin, culture conditions and gene expression patterns.
- P. Lonergan, D. Rizos, A. Gutiérrez-Adán, T. Fair, M. Boland
- BiologyReproduction in domestic animals = Zuchthygiene
- 1 August 2003
Evidence for an effect of oocyte origin and/or in vitro maturation conditions on the developmental capacity and gene expression patterns in the oocyte is demonstrated and the well-documented effects of post-fertilization culture environment on embryo gene expression and quality are highlighted.
Developmental, qualitative, and ultrastructural differences between ovine and bovine embryos produced in vivo or in vitro
- D. Rizos, T. Fair, S. Papadopoulos, M. Boland, P. Lonergan
- Biology, MedicineMolecular Reproduction and Development
- 1 July 2002
The quality of ovine blastocysts was significantly higher than their bovine counterparts produced under identical in vitro conditions suggesting inherent species differences between these two groups affecting embryo quality.