EFFECT OF UTERUS POSITION RELATIVE TO THE PELVIC INLET ON THE ACCURACY OF EARLY BOVINE PREGNANCY DIAGNOSIS BY MEANS OF ULTRASONOGRAPHY

A 5-MHz sector transducer (experiment 1) and a 7.5 MHz linear-array tr ansducer (experiment 2) were used for early pregnancy diagnosis in two Hungarian dairy herds under field conditions. In the first experiment , ultrasound scanning was conducted three times at 3 or 4-day interval s between 24 and 33 days after artificial insemination (AI), while in the second experiment, it was performed two times at 7-day intervals b etween 27 and 38 days post-insemination. Signifi-cantly more incorrect non-pregnancy diagnoses were made between 24 and 33 days (first exper iment) and between 27 and 38 days (second experiment) after AI in cows in which the uterus was located far cranial to the pelvic inlet than in animals in which the uterus was located within or close to the pelv ic inlet at the first ultrasonographic examination.