RESUMO
This study determined the ovarian, uterine, and luteal hemodynamic variations using Doppler between pregnant and non-pregnant pluriparous buffalos in relation to their anatomical and histological basics during the first 31 days after natural mating. Adult healthy cyclic Egyptian buffalo (n = 10) were selected and categorized into two groups; group 1 (n = 5) was mated naturally by a fertile bull during the late estrus phase, and group 2 (n = 5) was not mated. Animals were subjected to Doppler ultrasonography to evaluate luteal, ovarian, and uterine blood flows from day 7 until day 31 post-mating. Besides, three pregnant (one month) and other non-pregnant uterus (n = 6) were obtained from a local abattoir to study the anatomical and histological features. Our results revealed that the luteal, ovarian, and uterine arteries cross-sectional diameters/mm increased (P < 0.05) from day 7 till day 31. Resistance (RI) and pulsatility indices (PI) decreased linearly (P < 0.05) in pregnant buffalos till day 31, but the peak systolic, end diastolic velocities and flow volume of those arteries were increased. Additionally, luteal colored areas away and toward CL were increased (P < 0.05) in the pregnant group compared to non-pregnant ones. There was a significant (P < 0.05) increase in the lumen diameter of luteal, ovarian, and uterine artery sections in pregnant buffalos compared to those of non-pregnant ones. While the mean value of tunica media's thickness of both luteal and uterine artery was significantly higher in non-pregnant buffalos than pregnant ones, except for that of the ovarian artery. Additionally, the ovarian and uterine artery tunica muscularis relative area % was (P < 0.05) higher in pregnant buffalos than in non-pregnant ones, except for that of the luteal artery. It was concluded that in pregnant buffalos, ovarian, uterine, and luteal blood flows were improved from the first week until 31 days post-mating via a decline in both Doppler indices with an increase in Doppler velocities and blood flow volume in relation to their histological changes based on their anatomical architecture in comparison to non-pregnant one.
