Correlation of Prostatic Artery Blood Flow Assessed by Doppler Ultrasonography with Semen Characteristics in Beagle Dogs

SIMPLE SUMMARY: This study examined the blood flow parameters of the prostate artery before dog ejaculation assessed by pulsed-wave Doppler ultrasound (PwD) changes. The main objective of this study was to characterize the vascular parameters of the prostatic artery in beagle dogs and to explore the potential use of Doppler ultrasonography as a complementary method in dog stud selection. These findings report differences between blood flow parameters in cranial and caudal locations of the prostatic artery in comparison to subcapsular and parenchymal locations. There was a high positive correlation of peak systolic velocity with total volume and sperm concentration. In conclusion, estimation of the PwD parameters of the cranial prostatic artery may be useful in the breeding evaluation of dogs. ABSTRACT: Pulsed-wave Doppler ultrasonography (PwD) is a method used to rapidly and noninvasively assess blood flow dynamics of the canine prostate. Modifications in gland vascularization can affect seminal plasma production and consequently sperm quality. The aim of this study was to determine the normal blood flow parameters of the prostate artery in beagle dogs and to analyze the correlations between vascular flow and semen quality characteristics. PwD was performed on five beagle dogs (5–6 years) measuring vascular features in four different locations of the prostatic artery (cranial, subcapsular, parenchymal and caudal); the measured features were peak systolic velocity (PSV), end-diastolic velocity (EDV), resistive index (RI) and pulsatility index (PI). Ejaculates were obtained using digital manipulation and semen quality was evaluated by determining macroscopic (total volume, sperm-rich fraction volume, color and pH) and microscopic (sperm motility, morphology, viability and acrosome integrity) characteristics. The values of PSV, PI and RI in cranial and caudal prostatic arteries were significantly higher than in subcapsular and parenchymal arteries (p < 0.05). Moreover, a positive correlation of PSV value in the cranial region of the prostatic artery with total ejaculate volume (p < 0.01, r = 0.612) and sperm concentration (p < 0.01, r = 0.587) was determined. PI index was negatively correlated with sperm concentration (p < 0.01, r = −0.709). In conclusion, the results suggest that the prostatic artery blood flow parameters can affect macroscopic semen quality characteristics in healthy dogs.