Effects of increasing n3:n6 ratio by replacing extruded soybeans with extruded flaxseed on dry matter intake, rumen fluid bacteria, and liver lipid metabolism in transition cows

Comparative Evaluation of Takhrai (Cymbopogon citratus) Leaf Extracts with Commercial Antioxidants for Oxidative Stress Mitigation in Ruminants Under Heat Stress

This investigation presents a rigorous comparative evaluation of methanolic and hexanoic extracts from Takhrai (Cymbopogon citratus) leaves against commercial antioxidants for mitigating oxidative stress in heat-stressed ruminants. Phytochemical profiling revealed significantly higher concentrations of bioactive compounds in methanolic extracts, particularly ascorbic acid (2.12 ± 0.08 mg/g), sinapic acid (0.71 ± 0.03 mg/g), and apigenin (0.38 ± 0.02 mg/g). Methanolic extracts demonstrated exceptional antioxidant activities (DPPH IC50 = 36.62 ± 0.65 μg/mL), superior erythrocyte protection (hemoglobin oxidation IC50 = 12.06 ± 0.29 μg/mL), and robust Nrf2 pathway activation (HO-1 induction = 3.42 ± 0.17-fold). Metabolomic analyses revealed preservation of glutathione metabolism and attenuation of lipid peroxidation product accumulation. Immunomodulatory assessment demonstrated significant reduction of pro-inflammatory cytokines (TNF-α reduced by 54.3 ± 4.8%) and enhancement of anti-inflammatory mediators following LPS challenge. While storage stability presented limitations at ambient conditions (52.4 ± 3.7% activity retention after 6 months), refrigeration substantially improved preservation (92.3 ± 2.8%). Comprehensive effectiveness ranking across twelve parameters positioned methanolic extracts (mean score 1.7) comparable to vitamin E (1.6) and superior to other interventions. Collectively, these findings establish methanolic Takhrai extracts as promising sustainable alternatives to commercial antioxidants, with particular relevance for ruminant production in tropical regions.