s / Placenta 35 (2014) A1eA112 A23 molecules in the fetal epithelium, and in the placental angiogenesis, despite the large distribution of the CAVs -1 and -2 in water buffalo placenta. Funding: FAPESP P1.40. DEVELOPMENT OF THE SUBPLACENTA IN GALEA SPIXII (RODENTIA, CAVIIDAE) Ferdinando Bezerra , Phelipe Favaron , Andrea Mess , Maria Angelica Miglino , Moacir de Oliveira a Department of Animal Science, Universidade Federal Rural do SemiArido, Mossoro, Rio Grande do Norte, Brazil; b Surgery Department, University of Sao Paulo, Sao Paulo, SP, Brazil The subplacenta of caviomorph rodents is considered to be the developmental origin for trophoblast invasion, which is relatively similar to the process in human beings. Objectives: We described subplacental development in a cavy species, Galea spixii. Methods: Tissues were collected from 12 females, ranging from day 15 to 55 of gestation. Samples were processed by means of histology, immunohistochemistry, cytochemistry, and electron microscopy. Results: On day 15 to 23, the subplacenta consisted of a single cytotrophoblast layer and a syncytium lining the maternal lacunae. Fetal circulation was present. On day 30, the subplacenta was more compact with well-defined border. Then it showed intense vascularisation. The lobules were composed by syncytiotrophoblast in the central part, and mesenchyme surrounded by cytotrophoblast at the borders of the organ. On day 45, degeneration of tissues was evident and syncytiotrophoblast was more abundant than cytotrophoblast. The syncytium was vacuolized and showed signs of apoptosis. Near term (days 53-55), more evident signs of cell death and reduction of subplacental tissue occurred. Proliferative activity of the subplacenta, evaluated by PCNA and AgNOR, was high early in early gestation and then continously decreased. Conclusion: In conclusion, the development of the subplacenta in Galea started early on reached a maximum around day 30 and became necrotic towards the end of gestation. Financial support: INCTC and NETCEM. P1.41-N. MORPHOLOGICAL AND VASCULAR CHANGES IN THE CORPUS LUTEUM DURING EARLY GESTATION OF BOVINE SCNT-DERIVED PREGNANCIES F abio Pinaffi, Izabelle Jardim, Juliano Sangalli, Rafael Sampaio, Flavio Meirelles, Luciano Silva University of Sao Paulo, Pirassununga, Sao Paulo,