USO DE VARIáVEIS RELACIONADAS COM A PRODU O EMBRIONáRIA, EM CAMUNDONGOS, COMO FATORES PREDITIVOS

Mouse embryo production by superstimulation is a multifactorial process. To minimize the number of sacrificed animals and to maximize the results of the superstimulatory treatment, it should be possible to predict the risk of do not get embryos from such a treated animal. This work aimed to evaluate if the variables - hormone concentration and the timing of its administration, the copulatory plug presence and individual male used to mating – could be predictive factors on the mouse embryo production. Females were distributed in four groups (cross-over design) related to scheduled superstimulation treatment (1300h or 1700h) and eCG/hCG administered concentration (5 or 10IU). After the hCG treatment, females were put to mate. On the next morning it was verified the presence of a copulatory plug (D0.5). Embryo recovery was performed from D2.5 to D4.5 by flushing the oviducts and uterine horns. Total structures recovered (TSR) and the viable embryos (VE) were classified by its morphology. Viability rate (VR) was calculated with VE in relation to TSR (x100). Group comparison was analyzed with 5% of significance. There were no significant differences among groups, even when only main effects were analyzed (hormone concentration and timing of its administration). There was significant difference in VR from animals with or without plug and from the worst and best males used. It was concluded that neither the hormone concentration nor timing of its administration - or their association – was significant as predictive factors for the embryo production. However, the plug presence was related to higher VR.