03493nam a2200217 a 450000100080000000500110000800800410001910000200006024501240008026000590020452028450026365000110310865000190311965000200313865000110315865000200316965300270318970000190321670000220323570000180325719622862021-09-08       1997    bl uuuu     u00u1 u    #d1 aBRACKETT, B. G.  aInfluences of culture components on the development of bovine blastocysts in defined conditions.h[electronic resource]  aTheriogenology, v. 47, n. 1, p. 274, Jan., 1997.c1997  aAbstract: Experiments were conducted to determine influences on in vitro production (IVP) of bovine embryos of glucose (glc), citrate (c), glutathione (GSH), and growth factors, EGF and PDGF, during 9 d culture in defined conditions. Oocytes, aspirated from follicles (2-5 mm) at slaughter, with homogeneous cytoplasm and 2-3 layers of cumulus cells were washed twice in Tyrodes with 400 mug PVA/ml and 112 mug sodium pyruvate/ml and incubated in 100 mul of mTCM 199 + 10 mug oFSH and 5 mug bLH (NHPP, NIDDK, NICHD, USDA)/ml for 24 h before insemination. Then, after 6 h co-culture with heparin-capacitated sperm, ova were cultured in 50 mul drops of either c-SOF+NEA (control) (Biol.Reprod. 52:1410-1417) or c-SOF+NEA without glc and c (I), or without glc (II) for 5 d; then, developing embryos were transferred into c-SOF+NEA +/- GSH for 4 d. In another trial EGF or PDGF were added to c-SOF+NEA for the last 4 d. Culture media were renewed (50% by volume) every 24 h. Proportions of oocytes that cleaved (C) by 48 h, reached morulae (M) by 120 h, blastocysts (B) by 168 h, and expanded B (EB) by 216 h, and, of M that proceeded to B and EB were analyzed by ''Sigma Stat'' by means of ANOVA; differences among the treatments were analyzed by Bonferroni-t test. Removal of either glc and c, or glc, compromised results, e.g. C of 72.3 % for I, 64.8 % for II, and 86.1 % for control. Addition of GSH 5 d after beginning embryo culture was not beneficial for B development after initial culture in I, 31.3%, or II, 25.2%. Significantly more B and EB were obtained after 9 d in c-SOF+NEA (40.8 % and 34.1 %, P&lt0.05). Evaluation of development rates of d 5 M to B stages on d 7, 8, 9 revealed more M cultured in I followed by no GSH reached growing B stage by d 7 (27.3 %) than for other experimental groups (11.6 % for I with GSH, 14.9 % for II without GSH, and 18.9 % for II with GSH), but development was faster in c-SOF+NEA (39.6 %) (P&lt0.05). Early inclusion of citrate was found to enhance M to B development from d 5 to d 8 and, d 9 regardless of other treatments after d 5. In another experiment, different concentrations (0.05, 0.5, 5.0 ng/ml) of EGF or PDGF were added to c-SOF+NEA for the last 4 d of culture. The lowest concentration of either EGF or PDGF resulted in lower (P&lt0.05) blastocyst development (33.3 % for EGF and 46.6 % for PDGF) compared to the highest concentration (60.0 % and 80.0 %, respectively). EB development was significantly higher (P&lt0.05) in media containing either growth factor at 5 ng/ml; 32 of 60 M (53.3 %) reached EB with EGF, and 28 (46.6 %) of 60 M reached EB with PDGF present during the final 4 d. Results demonstrated positive influences of glc and c, absence of beneficial effect of GSH, variable patterns in M to B progression, and efficacy of EGF and PDGF in enhancing EB development.  aCattle  aEmbryo culture  aembryo transfer  aBovino  aEmbrião animal  aTecnologia de embrião1 aKESKINTEPE, L.1 aSIMPLÍCIO, A. A.1 aLUVONI, G. G.