Effect of dietary supplementation with hydroponic green barley fodder on rabbit performance, antioxidant capacity and total phenolic compounds in meat

Rabbit meat stands out as a nutritious low-fat protein source rich in essential amino acids, vitamins, and minerals, yet its production faces challenges from high feed costs and environmental impacts. Hydroponic green barley fodder (HGBF) emerges as a promising sustainable alternative, offering rapid growth, enhanced nutrient profiles including antioxidants, and reduced resource demands. This study aimed to evaluate the effects of dietary HGBF supplementation, with or without hydrogen peroxide (H2O2) seed pre-treatment, on rabbit performance, meat antioxidant capacity, and total phenolic compounds. Sixty-three post-weaned New Zealand rabbits (initial weight: 606 g) were divided into three groups for 42 days: T1 (100% pellets, control), T2 (50% pellets + 50% HGBF at 75 mM H2O2 pre-treatment), and T3 (50% pellets + 50% HGBF), All treatments were ad libitum. Carcass yields were assessed post-slaughter, while meat samples underwent 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•+) assays for antioxidant activity, enzymatic evaluations (catalase, superoxide dismutase, phenylalanine ammonia-lyase), and Folin-Ciocalteu method for phenolics. Results revealed no significant differences in hot or cold carcass weights across treatments, averaging below export standards due to the rabbits' young age. However, T2 diet significantly boosted total phenolic content (P < 0.05) and antioxidant capacity via DPPH (97.52% inhibition) and ABTS•+ (84.07% inhibition) compared to T1 and T3 groups with lower catalase activity indicating reduced oxidative stress. Enzymatic activities for superoxide dismutase and phenylalanine ammonia-lyase remained unaffected. These findings underscore HGBF with H2O2 pre-treatment as an effective strategy to enhance meat quality through elevated phenolics and antioxidants, fostering oxidative stability and nutritional value while promoting eco-friendly rabbit farming practices for broader livestock sustainability.