SUMMARY The aim of this study was to investigate the embryonic development and the age of the pregnancy, in which may firstly be detected by ultrasound. One hundred and forty two cows, performing two groups were submitted to echographic examination for pregnancy diagnosis. A Pie Medical Inc. scanner Mod. 450 with a 5MHz linear array transducer and a printer were used for echographic purposes. In the first group constituted of 12 charolais cows were studied some characteristics of the fetal anatomy from the 10th to the 50th day. The first detection of the subsequent structures was made in the following days: embryonic vesicle (18.0 ± 0.7); embryo proper (24.1 ± 0.5); heartbeat (26.2 ± 0.6); amnion (30.7 ± 0.7); limbs (32.7 ± 0.6); vertebres (40.2 ± 0.7); fetal movements(45.6 ± 0.5). In the second group constituted of 130 cross bred charolais cows the embryonic development from the 23rd to the 50th day of gestation was observed. In this period the embryonic vesicle reached a diameter of 46.4mm with a daily growth of 38mm and the embryo, a length (crown-rump) of 36.4rnm with a daily increase of 1.15mm (P<0.0001). The eariy pregnancy diagnosis as well as the monitoring of gestation, is feasible through uttrasonography.
ultrasonography; cows; pregnancy diagnosis
