Twelve growing Shami heifers available in Dier-Al-Hajar Station for
improving Shami Cattle weighing 115±3 kg and 178±4 days old were used to
monitor the daily growth of ovarian follicles (daily numbers, size, length and
number of waves, rate of gr
owth and regression) using Transrectal Ultrasound
Echo System (7.5 MHz probe) in 6-14 months-old heifers. Results indicated that
ovarian follicles developed in a wave pattern in all Shami heifers when they
were 6 months old and no significant differences in the number and size of
ovarian follicles were found between right and left ovaries. A cohort of 4 to 7
small follicles with a diameter 2-5 mm developed together and one of them was
selected for continual growth, became dominant and later regressed during the
pre-pubertal stage.