In this study, the influence of supra-nutritional organic selenium (Se) supplement on hematology and plasma biochemicals, including antioxidant parameters and plasma reproductive hormones, as well as blood flow characteristics in the supratesticular and common carotid arteries (STA and CCA, respectively) were investigated. For this purpose, 15 male goats were used and classified into three equal groups according to the supplementation of the basal diet (BD): negative control (NC), probiotic (Pro), and Se-probiotic (Se-Pro) groups. Blood perfusion in the STA and CCA was assessed by Doppler ultrasonography at three different time intervals: at the experimental onset (T0), 3 weeks of dietary supplement (T3), and after 6 weeks of observation (T6). Concomitantly, blood samples were withdrawn for hematobiochemical and hormonal changes. Results revealed no evidence of clinical abnormality, with some enhanced hematological parameters and antioxidant (SOD and GPX) levels in goats of the Se-Pro and Pro groups. High concentrations of FSH were found in the Se-Pro at T6 compared to its values in other groups. Similarly, testosterone levels were elevated in the Pro and Se-Pro groups at T3 compared to other time points. There were significant increases in levels of IGF-1 in the Pro and Se-Pro groups compared to the NC group. Significant (P < 0.05) increases in the values of the blood volume within the CCA and the STA were noted in the Se-Pro group, and the highest values were observed at T6 (CCA, 427.4 ± 33 ml/min; STA, 49.9 ± 5.0 ml/min). In conclusion, supra-nutritional organic selenium improves some hematobiochemical parameters, reproductive hormones, and the blood perfusion within the CCA and STA in goats.