Some factors affecting the efficacy of oviduct tissue-conditioned medium for the culture of early bovine embryos

摘要

Summary. Oviduct tissue-conditioned medium was evaluated for the culture of IVM-IVF bovine zygotes to the compact morula (cM) and blastocyst (BL) stages. Development was unaffected (P > 0·50) by freezing and thawing of conditioned medium: no. cM + BLo. cleaved ova obtained after culture in nonfrozen, frozen–thawed, and control treatments were 31/148 (21%), 26/124 (21%) and 5/86 (6%), respectively. The greatest proportion of normal development was obtained after a conditioning period of 48 h (P 0·75); no. cM + BLo. cleaved ova was 21/63 (33%) at oestrus and 21/79 (27%) in the luteal phase.