Effects of extracts on ruminal fermentation characteristics, methanogenesis, and microbial populations.

OBJECTIVE

(Lamouroux) is a red alga belonging to the family and is commonly found in the shallow coasts of many East Asian countries, including Korea, China, and Japan. has traditionally been utilized as an edible alga, and has various biological activities. The objective of this study was to determine whether dietary supplementation of could be useful for improving ruminal fermentation.

METHODS

As assessed by fermentation parameters such as pH, total gas, volatile fatty acid (VFA) production, gas profile (methane, carbon dioxide, hydrogen, and ammonia), and microbial growth rate was compared to a basal diet with timothy hay. Cannulated Holstein cows were used as rumen fluid donors and 15 mL rumen fluid: buffer (1:2) was incubated for up to 72 h with four treatments with three replicates. The treatments were: control (timothy only), basal diet with 1% extract, basal diet with 3% extract, and basal diet with 5% extract.

RESULTS

Overall, the results of our study indicate that supplementation is potentially useful for improving ruminant growth performance, via increased total gas and VFA production, but does come with some undesirable effects, such as increasing pH, ammonia concentration, and methane production. In particular, real-time polymerase chain reaction indicated that the methanogenic archaea and populations were significantly reduced, while the populations were significantly increased at 24 h, when supplemented with extracts as compared with controls.

CONCLUSION

More research is required to elucidate what supplementation can do to improve growth performance, and its effect on methane production in ruminants.