Seasonal variation in testicular blood flow dynamics and their relation to systemic and testicular oxidant/antioxidant biomarkers and androgens in rams

Abstract

The environmental temperature increased during summer and decreased during winter to the limits that might negatively affect animal and human reproduction. The responses of Egyptian rams to either hot or cold climatic conditions were studied in six mature rams subjected to weekly testicular Doppler ultrasonographic examination, blood sampling, seminal plasma collection and semen evaluation. The maximum environmental temperature and the relative humidity were used to classify the climatic condition according to the heat stress equation of sheep into hot months where temperature–humidity index (THI) was >26 (31.67 ± 0.54), and cold months where THI was <22 (18.39 ± 0.41). Testosterone, estradiol, superoxide dismutase (SOD), glutathione peroxidase (GPX) and lipid peroxide product (malondialdehyde, MDA) were measured in both blood and seminal plasma, while catalase (CAT) and reduced glutathione (GSH) were measured in blood and seminal plasma, respectively. Results revealed that, during the hot months, rams displayed significantly decreased testicular blood flow, increased seminal plasma MDA, decreased seminal plasma (SOD, GPx and GSH) and blood CAT antioxidant enzymes. The present study evidenced two novel findings: (a) the marked decrease in testicular blood flow volume, that is remarkable increase in both resistive index (RI) and pulsatility index (PI) values, during hot months could be negatively affected both seminal plasma enzymatic activities and seminal attributes, and (b) the SOD and GPx activities in seminal plasma of such animals were suitable predictive markers for seminal attribute evaluation.

Exogenous oxytocin administration improves the testicular blood flow in rams

“…In the last few years, several studies demonstrated the application of testicular pulsed wave Doppler Ultrasonography as a noninvasive and rapid valuable technique to evaluate the reproductive performance in farm animals (Fávaro et al, 2020;Hedia et al, 2019Hedia et al, , 2020b.…”

“…In the last few years, several studies demonstrated the application of testicular pulsed wave Doppler Ultrasonography as a noninvasive and rapid valuable technique to evaluate the reproductive performance in farm animals (Fávaro et al., 2020; Hedia et al., 2019, 2020b). Testis as a highly compact organ requires a continuous and constant blood flow through the corresponding testicular artery to precisely perform its endocrine (steroidogenesis) and exocrine (sperm production) functions.…”

“…After, the presentation of the spectral layout of the supratesticular artery (Figure 2), the parameters examined were peak systolic velocity (PSV), end‐diastolic velocity (EDV), resistive index (RI = (PSV‐EDV)/PSV) and pulsatility index (PI = (PSV‐EDV)/mean velocity). For each parameter, two to four measurements were registered in different areas of interest along the supratesticular artery path (Batissaco et al., 2013; Hedia et al., 2020b).…”

“…For each parameter, two to four measurements were registered in different areas of interest along the supratesticular artery path (Batissaco et al, 2013;Hedia et al, 2020b).…”

Melatonin improves testicular haemodynamics, echotexture and testosterone production in Ossimi rams during the breeding season

“…This experiment was conducted in the Department of Theriogenology, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt, from December 2020 to February 2021 (physiological breeding season in Egypt; Hedia et al., 2020). The Animal Care and Ethical Use Committee of the Faculty of Veterinary Medicine at the Cairo University reviewed and approved the experimental protocol (VetCU28042021264).…”