Effects of Cumulus Cells on in vitro Fertilization of Bovine

Key words Cumulus cells; in vitro fertilization; Co-culture; Melatonin; OPU; Cleavage rate; Blastocyst rate (ProQuest: ... denotes non-USASCII text omitted.) Embryo in vitro production plays an important role in the production of dairy cows and beef cattle. Methods Oocytes collection The cattle used for the test, namely Simmental and wagy F-,, were from the cattle farm of second base for experiment of the Heilongjiang Animal Science Institute, aged 1 -4 years old with normal estrous cycle, and no abnormality was found in the ovaire after transrectal ultrasonography. First of all, keep the cows standing to clear the rectal feces and clean the vulva, and then the 0.1% bromo-geramine was used to disinfect the vulva. After washing for twice in the embryo culture solution CR1aa, the zygotes were removed to the culture drops which had been equilibrated in the incubator for 2 h. and then 2025 zygotes were put into the 100 pi of embryo culture solution CR1aa (2% of essential amino acid, 1% of non essential amino acids, 2 mmol/L of glutamine, 3 mg/ml of bovine serum albumin, 10 ng/ml of epidermal growth factor), and cultured in vitro in the saturated humidity incubator with 5% C02 at the temperature of 38.5 °C for 7-9 d. The cleavage rate was recorded at the 4641 h, and the culture solution was changed in half amount every 48 h. the blastocyst rate was recorded at the 7th_9th d Statistical analysis The SPSS statistical software @Independent-samples t test and One-way ANOVA were used for the analysis of variance.