CONCLUSION

Supplementation with LGP at 150 g/head/day, representing approximately 2.5% of total dietary DM, improved rumen fermentation efficiency in Thai native beef cattle by increasing DM and neutral detergent fiber digestibility, enhancing propionate production, increasing bacterial populations, and improving microbial protein synthesis. In addition, LGP reduced protozoal populations and estimated CH4 production without affecting feed intake, ruminal pH, NH3-N, or BUN concentrations. No clinical signs of mimosine toxicity were observed, indicating that the pelleted formulation and controlled supplementation level were well tolerated.

These findings suggest that LGP is a practical phytogenic feed additive for tropical beef production systems, particularly for cattle maintained on low-quality rice straw-based diets. The major strength of this study is the development of a locally available, low-cost, and easy-to-produce pelleted formulation that combines the complementary bioactive effects of L. leucocephala and ginger.

However, the study was limited by its short experimental duration, small sample size, inclusion of only female cattle, indirect estimation of CH4 production, and lack of quantification of residual mimosine and ginger bioactive compounds. Future long-term in vivo studies should include direct CH4 measurements, evaluation of growth and carcass performance, mimosine safety assessment, pellet quality testing, and molecular analysis of the rumen microbiota.

Overall, LGP offers a promising, scalable, and environmentally sustainable strategy to improve rumen function, enhance microbial protein synthesis, and reduce enteric CH4 emissions in tropical beef cattle production.