ANSC 3323 Lecture Notes - Lecture 3: Inner Cell Mass, In Vitro Fertilisation, Pregnancy Rate
Document Summary
Blastocysts, pregnancy rate of ivf, los in cattle. Blastocyst: trophoblast, blastocoele, inner cell mass (embryoblast, in the uterus. Differentiation: an unspecialized cell gives rise to specialized cells, no changes in genes, caused by changes in gene expression, first differentiation in development. Inner cell mass (form fetus) vs. trophectoderm (form placenta: totipotency, pluripotency. In vitro embryo culture: culture medium must mimic changing oviduct and uterine environment for optimal development, commercial labs use sequential media. Steps of embryo in vitro production (ivp: collection of oocytes from ovaries. Opu: oocyte ivm (24 hours, process frozen sperm. Capacitation: in vitro fertilization (6 hours, produces zygotes, in vitro embryo culture (7 days, blastocysts) Pregnancy rates of embryos (higher for humans: cattle. 10% of embryos are polyspermic (30% in pigs) Large offspring syndrome (los: heavier at birth, difficulty at delivery, difficulty standing, reluctant to suckle, respiratory problems, hypothermia, neonatal death, large placenta.
