Embryo technology: implications for fertility in cattle.
During the past thirty years, basic and experimental studies on classical (superovulation; non-surgical recovery and transfer of cattle embryos) and advanced embryo technologies (in vitro embryo production; cloning by somatic cell nuclear transfer) have generated structural and functional information on oocyte development and quality, fertilisation and conceptus development. This information has provided new insight, not only into these technologies per se but also into the factors contributing to fertility in cattle. It is now known that the peripheral and follicular endocrine profiles have a profound influence on the subsequent developmental competence of the embryo. It is also well established that manipulation of the oocytes or embryos may adversely affect embryonic and foetal development, leading to the so-called 'large offspring syndrome'. Information from such studies has alerted scientists to the importance of epigenetics in cattle reproduction.
Greve
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T
Royal Veterinary and Agricultural University, Department of Large Animal Sciences, Dyrlaegevej 68, 1870 Frederiksberg C, Denmark.
Callesen
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H
D000818:Animals; D001947:Breeding / Q000379:methods* / Q000592:standards; D002417:Cattle / Q000196:embryology* / Q000235:genetics / Q000502:physiology; D019976:Cloning, Organism; D004624:Embryo Transfer / Q000662:veterinary; D047108:Embryonic Development; D005260:Female; D005298:Fertility / Q000502:physiology*; D008297:Male; D011247:Pregnancy; D012098:Reproduction / Q000502:physiology*; D013480:Superovulation