Canine reproductive ultrasound examination for predicting future sperm quality

Abstract

ContentsThe reproductive potential of male animals is commonly evaluated using a breeding soundness examination incorporating B-mode ultrasound examination of the testes and recently Doppler ultrasound examination of the testicular arteries. These techniques may detect testicular normality or pathology, and while some measured parameters are associated with semen quality at the time of ultrasound examination, few studies have investigated the relationship with future semen quality. We hypothesized that B-mode and Doppler ultrasound measurements would correlate with future semen quality. Within two studies, we investigated the relationship between ultrasound measured testicular volume, testicular echogenicity, testicular homogeneity, subjective assessment of the testicular parenchyma, testicular artery resistance index, and pulsatility index with subsequent semen quality. Fifty-five normal fertile dogs of which 29 had stable semen quality and 26 had a subsequent decline in semen quality were examined during a 6-month period commencing 62 days after the ultrasound examination.Statistical analysis showed that no ultrasound parameters were predictive of future total sperm output or percentage live normal sperm. However, mean testicular echogenicity was positively related to future sperm motility (t = 2.202, p = .039). We conclude that quantitative ultrasound assessment of the appearance of the testicular parenchyma has potential for the evaluation of future semen quality in dogs.

Can testicular artery Doppler velocimetry values change according to the measured region in dogs?

“…The hemodynamic study of five regions of the testicular artery allowed for the identification of different wave patterns as well as different Doppler velocimetric values (PSV, EDV, RI and PI). The B‐mode enabled an evaluation of testicular architecture, which was in line with previous studies indicating that this method allows an accurate evaluation of the volume, position, contours, shape, echogenicity and ecotexture of the testicular parenchyma, and Doppler allowed for the study of the distribution and nature of hemodynamics in the testes (England, ; England et al, ; Paltiel et al, ), which could provide essential information for the study of affections, such as neoplasia, testicular twists and ectopic testicles (Davidson & Baker, ; England, ; Felumlee et al, ; Johnston, Feeney, Johnston, & O'Brien, ).…”

“…The PSV, EDV, PI and RI were analysed and automatically calculated by the device in three previously reported regions of the testicular artery (distal supratesticular, marginal and intratesticular) (England et al, ; Souza, England et al, ; Souza, Cunha Barbosa et al, ; Zelli et al, ) and two new proposed regions (proximal supratesticular and medial supratesticular), as shown in Figure .…”

“…Testicular artery blood flow can be measured using radioactive microspheres (Noordhuizen‐Stassen, De Jong, MacDonald, Schamhardt, & Wensing, ); however, modern methods such as Doppler ultrasonography have been described in men, other domestic species and, more recently, dogs (de Brito et al, ; England et al, ; Gloria et al, ; Ortiz‐Rodriguez et al, ; Sakamoto et al, ; Souza, Cunha Barbosa et al, ; Zelli, Troisi, Elad Ngonput, Cardinali, & Polisca, ).…”

“…The literature describes three regions of blood flow measurement in the testicular artery of dogs: the supratesticular region (in the spermatic cord), the marginal region (of the testis) and the intratesticular region (Carrillo, Soler, Lucas, & Agut, ; England et al, ; Gumbsch, Gabler, & Holzmann, ; Gunzel‐Apel, Mohrke, & Poulsen Nautrup, ; Souza, Cunha Barbosa et al, ; Zelli et al, ).…”

Genomewide association of male reproductive traits in Aksaray Malakli dogs

“…With regard to phenotypic reproductive traits, an increase in testicular size with age was reported by some authors (Akçay & Tekin, 2002;Bhanmeechao, Srisuwatanasagul, Prapaiwan, & Ponglowhapan, 2018;England et al, 2017). Some researchers stated that the quality of semen decreases as the age of the animals increases (Eskenazi et al, 2003;Rijsselaere et al, 2007).…”