Influence of black Maca (Lepidium meyenii Walp.) nano-emulsion on growth parameters, circulating testosterone, testicular vascular dynamics, and antioxidant defences in New Zealand white rabbit bucks

Maca (Lepidium meyenii Walp.) has been widely employed in health products and cosmetics because of its numerous pharmacological benefits, including the promotion of sperm fertility as well as antioxidant and anti-inflammatory activity. Researchers have worked on identifying and screening natural compounds from various plant species to avoid synthetic antioxidants and their potential side effects. This study was conducted to investigate the potential benefits of oral administration of black Maca nano-emulsion (BMNE) twice weekly for ten weeks on body weight, serum testosterone levels, testicular blood flow, and antioxidant capacity in rabbit bucks. Twenty New Zealand white (NZW) rabbit bucks were enrolled in this experiment. Rabbits were allocated into two groups: a control group (M0, 0 mg) and a treated group (M60, 60 mg Maca nano-emulsion). The body weight of each rabbit was recorded fortnightly using a digital balance. Testosterone levels, antioxidants, and Doppler parameters were also assessed at biweekly intervals until the end of the experiment. Results revealed that control rabbits (M0) had significantly lower (P < 0.05) body weights (2809.07 ± 35.29 vs. 3204.60 ± 59.80 gm) and testosterone levels (0.45 ± 0.03 vs. 1.50 ± 0.18 ng/ml) than the M60 group. The resistive index (RI), pulsatility index (PI), and systolic/diastolic ratio (S/D) were low (P < 0.01) in the M60-treated group, especially at week 4 (W4), compared to the M0 group. Catalase and total antioxidant capacity had significantly increased (P < 0.05) in the M60-treated group compared to M0. Unexpectedly, malondialdehyde (MDA) increased starting from week 8 (W8) in the M60-treated group. In conclusion, Maca nano-emulsion can be recommended at a dose of 60 mg /buck / twice weekly for ten weeks to improve body weight, testosterone levels, and testicular blood supply as well as to enhance antioxidant capacity in New Zealand white bucks.