The chick embryo – past, present and future as a model system in developmental biology 1011 PART I: The chick as a classical system for the study of development L. Wolpert (UK) Much more from the chicken's egg than breakfast – a wonderful model system 1015 C. Tickle (UK) The contribution of chicken embryology to the understanding of vertebrate limb development 1019 L. Wittler, M. Kessel (German...

This review highlights the importance of energy and protein nutrition of the dam on embryo production and embryo development. Fertility is reduced by greater negative energy balance post-partum as manifest by reductions in fertility and embryo quality associated with lower body condition score (BCS) but particularly with greater postpartum loss of BCS. In addition, excessive energy intake, part...

The relationship between nutrition and reproduction in sheep has been the subject of research in several international groups. This review will particularly focus on the effects of undernutrition on the potential causes of reproductive failure including abnormalities of the ovum or the embryo, luteal inadequacy and failure of the supply of progesterone to the uterus, or the mechanisms involved ...

BACKGROUND It has been proposed that preimplantation embryo viability during culture and following embryo transfer is associated with a 'quiet' metabolism. Viable embryos may be better equipped to contend with damage to the genome, transcriptome and proteome, or they may possess less damage than non-viable embryos. METHODS Much of the data for the quiet embryo hypothesis was obtained in the h...

Culture of bovine embryos in the presence of insulin-like growth factor-1 (IGF-1) can increase pregnancy rates following transfer to heat-stressed, lactating dairy cows. The objective of the present experiment was to determine whether the effect of IGF-1 on post-transfer embryo survival was a general effect or one specific to heat stress. Lactating recipients (n=311) were synchronized for timed...

The normal intrauterine fluid environment is essential for embryo implantation. In hydrosalpinx patients, the implantation and pregnancy rates are markedly decreased after IVF-embryo transfer, while salpingectomy could significantly improve the pregnancy rates. The leakage of hydrosalpinx fluid into the endometrial cavity was supposed to be the major cause for impaired fertility. However, the u...

When evaluating the feasibility of a human embryo to implant in a woman uterus on In-Vitro Fertilization (IVF), one of the most important morphological parameters taken into account in the embryo selection process is the thickness of zona pellucida (i.e. the external layer of the embryo). Furthermore, the measurement of zona pellucida thickness variation is a potentially reliable parameter to e...

Based on experiments with cultured fibroblasts, the apoptosis regulators caspase-9 and Apaf-1 are hypothesized to function as tumor suppressors. To investigate their in vivo role in lymphomagenesis, an IgH enhancer-driven c-myc transgene was crossed onto Apaf-1(-/-) and caspase-9(-/-) mice. Due to perinatal lethality, Emu-myc transgenic Apaf-1(-/-) or caspase-9(-/-) fetal liver cells were used ...

Plants have duplicate versions of the oxidative pentose phosphate pathway (oxPPP) enzymes with a subset localized to the chloroplast. The chloroplast oxPPP provides NADPH and pentose sugars for multiple metabolic pathways. This study identified two loss-of-function alleles of the Zea mays (maize) chloroplast-localized oxPPP enzyme 6-phosphogluconate dehydrogenase (6PGDH). These mutations caused...