Potential use of Flemingia (Flemingia macrophylla) as a protein source fodder to improve nutrients digestibility, ruminal fermentation efficiency in beef cattle

OBJECTIVE: This study aimed at studying the potential use of Flemingia (Flemingia macrophylla) as a protein source fodder to improve nutrients digestibility and ruminal fermentation efficiency in beef cattle. METHODS: Four, Thai native beef cattle were randomly assigned in a 4×4 Latin square design. Four levels of Flemingia hay meal (FHM) were used to replace soybean meal (SBM) in the concentrate mixtures in four dietary treatments replacing levels at 0%, 30%, 60%, and 100% of SBM. RESULTS: The experimental findings revealed that replacements did not effect on intake of rice straw, concentrate and total dry matter (DM) intake (p>0.05). However, the apparent digestibilities of DM, organic matter, crude protein, acid detergent fiber, and neutral detergent fiber were linearly increased up to 100% replacement levels. Moreover, the production of total volatile fatty acids, and propionate concentration were enhanced (p<0.05) whereas the concentration of acetate was reduced in all replacement groups. Consequently, the CH(4) production was significantly lower when increasing levels of FHM for SBM (p<0.05). Furthermore, rumen bacterial population was additionally increased (p<0.05) while protozoal population was clearly decreased (p<0.05) in all replacement groups up to 100%. In addition, microbial nitrogen supply and efficiency of microbial nitrogen synthesis were enhanced (p<0.05), as affected by FHM replacements. CONCLUSION: The findings under this experiment suggest that 100% FHM replacement in concentrate mixture enhanced rumen fermentation efficiency, nutrients digestibilities, bacterial population, microbial protein synthesis, and subsequently reduced CH(4) production in beef cattle fed on rice straw.