Cleavage and Blastocyst Formation by Pig Eggs In Vitro2

Blastocyst formation by pig embryos resulting from in-vitro fertilization of oocytes matured in vitro

“…The culture system in the present study may therefore not have been suitable for embryos beyond the 3-cell stage. Since the detri¬ mental effects of lactate and pyruvate (Davis & Day, 1978;Davis, 1985) on pig embryos and the beneficial effects of reduced oxygen atmosphere (Wright, 1977) and co-culture with uterine fibro¬ blasts (Kuzan & Wright, 1982) on pig embryos have been reported, it will be necessary to examine these factors to improve the viability of pig embryos in vitro.…”

Development of rat one-cell embryos in a chemically defined medium: effects of glucose, phosphate and osmolarity

“…Developmental blocks occur in vitro at specific stages according to the species in hamster (Yanagimachi and Chang, 1964; Whittingham and Bavister, 1974;Bavister et al, 1983), mouse (Cross and Brinster, 1973;Goddard and Pratt, 1983; Biggers, 1987), bovine (Thibault, 1966) and pig (Davis and Day, 1978) embryos. Schini and Bavister (1988) reported that phosphate and glucose are responsible for the developmental block of hamster embryos at the two-cell stage in vitro.…”

Molecular and ultrastuctural changes of rat pre-implantation embryos during two-cell developmental arrest

“…In the mouse system, 2-cell block was successfully overcome by decreasing osmotic pressure of the culture media and supplementation of essential and non-essential amino acids [7][8][9]. Under suboptimal culture conditions, similar developmental block has been observed in pre-implantation embryos of other species at later stages of embryo development: 4-to 8-cell in human, 4-cell in pigs [10], and 8-to 16-cell in cattle and sheep [11]. The embryo development block often coincides with the time of genome activation in these species [12][13][14][15].…”