Relationship between angioarchitecture of the testicular artery and spermiogram parameters in Egyptian buffalo bulls (bubalus bubalis)

Seasonal Alterations in Testicular Hemodynamics and Echotexture in Relation to Semen Quality in Buffalo Bulls

The present study is aimed at investigating the usefulness of the pulsed-wave Doppler ultrasonography for the characterization of testicular blood flow in buffaloes during the nonbreeding and breeding seasons. Ten Egyptian buffalo bulls were evaluated for changes in the blood flow (Doppler’s indices: resistive index (RI) and pulsatility index (PI)) at the levels of supratesticular (STA) during the breeding (winter) and nonbreeding season (summer). The alterations in testicular parenchyma echotexture (pixel intensity (PIX) and echotexture heterogeneity (EH)) were assessed by computer analysis software. Circulating testosterone and nitric oxide (NO) concentrations and total antioxidant capacity (TAC) were measured colorimetrically. Sperm parameters including total and progressive motility %, viability %, morphology %, and concentrations were assessed. Results revealed lower values ( $p<0.05$ ) of RI ( $0.55\pm 0.02$ ) and PI ( $0.82\pm 0.03$ ) within the STA in the breeding period compared to the nonbreeding period (RI: $0.67\pm 0.03$ ; PI: $0.99\pm 0.01$ ). Higher ( $p<0.05$ ) PIX and EH were found in the nonbreeding season (PIX: $72.09\pm 1.81$ ; EH: $14.99\pm 1.37$ ) compared to the breeding season (PIX: $60.95\pm 1.51$ ; EH: $11.75\pm 0.63$ ). Concentrations of testosterone and TAC were not significantly changed. However, the concentrations of NO were greater ( $p<0.05$ ) during the breeding season ( $78.21\pm 0.87$ ) compared to those of the nonbreeding one ( $59.74\pm 2.97$ ). Total motility %, progressive motility %, viability %, and sperm concentrations were higher during the breeding season compared to that during the nonbreeding season ( $p<0.05$ ). In conclusion, seasonality alters testicular hemodynamics and echotexture, NO concentrations, and sperm quality in buffaloes without alterations in the testosterone and TAC levels.

Morphological and ultrasonographic characterization of the three zones of supratesticular region of testicular artery in Assaf rams

To fully understand the histological, morphometrical and heamodynamic variations of different supratesticular artery regions, 20 mature and healthy Assaf rams were examined through ultrasound and morphological studies. The testicular artery images of the spermatic cord as shown by B-mode analysis indicated a tortuous pattern along its course toward the testis, although it tends to be less tortuous close to the inguinal ring. Doppler velocimetric values showed a progressive decline in flow velocity, in addition to pulsatility and vessel resistivity when entering the testis, where there were significant differences in the Doppler indices and velocities among the different regions. The peak systolic velocity, pulsatility index and resistive index were higher in the proximal supratesticular artery region, followed by middle and distal ones, while the end diastolic velocity was higher in the distal supratesticular region. The total arterial blood flow and total arterial blood flow rate reported a progressive and significant increase along the testicular cord until entering the testis. Histological examination revealed presence of vasa vasorum in the tunica adventitia, with their diameter is higher in the proximal supratesticular zone than middle and distal ones. Morphometrically, the thickness of the supratesticular artery wall showed a significant decline downward toward the testis; meanwhile, the outer arterial diameter and inner luminal diameter displayed a significant increase distally. The expression of alpha smooth muscle actin and vimentin was higher in the tunica media of the proximal supratesticular artery zone than in middle and distal ones.