Effect of Gossypol on Bovine Blastocyst Attachment and Trophoblastic outgrowth in Vitro

The presont study was carried out to investigate the effect of different amounts of gossypol on bovineblastocyst attachment and trophoblastic outgrowth in vitro. Bovine oocyte were collected from theovaries of slaughtered cows and were matured and fertilized in vitro. Cleaved oocyte were culturedin CRlaa + BOEC and TC-199 + 10% FCS combined in an 1:1 ratio. After 8 days of co-culture,the hatched blastocysts were randomly allotted to different treatment groups. All were cultured ona fetal fibroblast monolaycr (prepared from bovine fetuses) in TC-199 culture medium supplementedwith 10% fetal calf serum (TCFCS). But the groups differed from one another in the dose ofgossypol given: 0.01 μg, 0.1 μg, 1 μg, 10 μs/ml, and no gossypol as control. All cultures wereperformed in 24-well culture plates at 39℃ with 5% CO_2 in air. The results indicate that the ratesof attached and outgrowing blastocysts in the medium containing 1 μg/ml gossypol were significantlylowcr than the control group (p<0.01) and outgrowth were inhibited by gossypol in a dose-dependent manner.

The Study on the Gene Expression of Preimplantation IVF Bovine Embryos

The cattle different stage embryos obtained from in vitro was studied using the technology of single preimplantation embryo mRNA different display:single 8-cell and blastocyst stage embryos were studied using technology of mRNA different display and one different fragment was found. The result suggested that this fragment displayed high homology (99%) to cattle mRNA for ribosomal protein L31. Then to detect the expression of RPL31mRNA in 8 cell and blastocyst stage embryos by real-time quantitative PCR,the result showed the relative amount of 8 cells was 3.2 times of blastocyst's.

Development of a Synthetic Medium for the in Vitro Culture of Bovine Embryos

The aim of this study was to develop a synthetic medium for the in vitro culture of bovine embryos, using various growth factors and cytokines （GF-CYK）： insulin-like growth factorl （IGF-Ⅰ）, insulin-like growth factorⅡ （IGF-Ⅱ）, basic fibroblast growth factor （bFGF）, leukemia inhibitory factor （LIF）, granulocyte-macrophage colony stimulating factor （GM-CSF） and transforming growth factor beta Ⅰ （TGF-β1） ＋ hyaluronan （HA） ＋ recombinant albumin （RA）. The embryos were cultured in synthetic oviduct fluid （SOF） supplemented with： treatment 1 （T1）： bovine serum albumin （BSA） ＋ insulin, transferrin and selenium （ITS） （control）; or treatment 2 （T2）： GF-CYK ＋ HA ＋ RA. The blastocyst rates were not significantly different between TI and T2, at seven days post fertilization （dpf） （28.9% ± 2.4% and 31.8% ±2.2%）, and at 8 dpf （36.5% ±2.4% and 39.1% ±1.9%）, respectively （P 〉 0.05）. The total cell number （TCN） was significantly higher with T2 than that with T1 at 7 dpf（164.9 ±5.3 and 149.7 ±4.0） and 8 dpf （182.7 ±6.4 and 165.0 ±5.5） （P 〈 0.05）. The blastocyst diameter obtained with T2 was significantly greater （P 〈 0.05） than with T1 at 7 dpf （173.3 μm ±4.9 μm and 157.2μm ±4.1 μm, respectively）, however, no significant differences were observed at 8 dpf （190.3 μm 5.2 μm and 179.7 μm ± 5.3 μm, respectively）. In conclusion, the synthetic medium （T2） shows a comparable development rate to the control medium and improves the blastocyst diameter and the TCN.