Preliminary observations on the effect of parity on first day ultrasonic detection of embryo and its organs in bovine

The aim of this study was to determine the effect of parity on the first day of ultrasonic detection of embryo and its organs using 8 MHz frequency. For this purpose, six nulliparous heifers, five primiparous cows and six multiparous cows of the Holstein breed were selected and mated by a single bull from the herd. From day 16 after mating, cows and heifers were examined by ultrasonography thrice weekly for the day of first detection of the embryo and its organs. The mean of first-day detection in heifers, primiparous and multiparous cows was as follows, respectively: allantois on days 22.3, 23 and 25.8; embryo proper on days 21.8, 23 and 27; heartbeat of embryo on days 26.1, 26.6 and 31.1; amnion on days 31, 31 and 30.8; limb buds on days 29.5, 28.8 and 30.6; stomach (abomasum) on days 32.2, 38.6 and 36.8; spinal column on days 32.6, 33.4 and 37.3; placentomes on days 33.3, 37 and 35.3; eyes on days 35.1, 35.4 and 38.6 and lens on days 40, 41.4 and 44. Although the mean of first day observation of all structures in heifers tends to be earlier than in the other groups, statistically, allantois, the embryo proper and its heartbeat in heifers and primipara were visualized significantly earlier than in multiparous cows. However, there were no differences between heifers and primiparous cows.