The aim of the present study was to examine the relation between follicular blood flow of the
ovulatory follicle and the levels of serum E2 and nitric oxide (NO) in Ossimi ewe. Seven cyclic
ewes were synchronized with a double injection PGF2. The follicular wave was examined
daily until ovulation (disappearance of the large dominant follicle ultrasonographically)
with transrectal color Doppler ultrasonography (8–10 MHz linear array transducer). The
number of recruited follicles was 4.8
±
0.9 (3–8 follicles) with diameter of 2.8
±
0.1 mm.
The interval from PGF2 injection to follicle deviation was 2.35
±
0.07 days. The diameter
of the first largest follicle (LF1) at recruitment day was 4
±
0.3 mm while the diameter
of the second largest follicle (LF2) was 3.7
±
0.1 mm. The diameter of LF1 at the day of
deviation was 5.1
±
0.5 mm while the diameter of the LF2 was 4
±
0.7 mm. The diameter of
the ovulatory follicle was 6.1
±
0.5 at day of ovulation. We detected the blood flow area of
the ovulatory follicle at D2. At ovulation, the blood flow area and blood flow area percent
increased significantly to be 11.9
±
0.6 mm2 and 44
±
3.4% respectively. The results showed
a positive correlation between E2 and NO (r = 0.85, P < 0.009). Both increased concomitantly
with the diameter of the ovulatory follicle. Besides, NO and E2 reached a maximum level at
ovulation (12.1
±
1.8 ng/ml and 16.4
±
1.7 pg/ml respectively).