Researchers from the Huazhong Agricultural University and University of Alberta have reported new findings on the use of Thymol as agent to reduce methane emission in ruminants.
Other works had already been performed on this topic, however there were inconsistencies regarding the effective dose of thymol, and the actual effect it has on the ruminal microbiota. Therefore, this research had two main objectives, namely the study of the main effects of thymol supplementation on rumen microbiota, and the identification of the most effective dose of thymol.
The experiment was performed in vitro. Reserchers incubated goat ruminal fluid with 0 mg/L, 100 mg/L, 200 mg/L, and 400 mg/L of thymol for 24 hours. They measured total gas production, methane, ammonia-nitrogen, VFAs, Total VFA, acetate/propionate ratio, in vitro dry matter digestibility, and in vitro organic matter digestibility. They also studied the composition of the ruminal microbiota and their interrelations.
The results showed that the optimal dose of thymol to reduce methane production is 200 mg/L, which is accompanied by a maintenance of ruminal activity and a change in microbiota (especially bacteria); higher doses compromiseed the ruminal function. They also reported that the decrease in methane production is due to lower abundance of especific bacteria, which reduces the availability of substrates to produce methane. Finally, scientists remark the need to continue researching on the interactions between different components of the ruminal microbiota in order to better understand their dynamics.
Reference
Yu, J., Cai, L., Zhang, J., Yang, A., Wang, Y., Zhang, L., Guan, L. L., & Qi, D. (2020). Effects of Thymol Supplementation on Goat Rumen Fermentation and Rumen Microbiota In Vitro. Microorganisms, 8(8), 1160. https://doi.org/10.3390/microorganisms8081160
The article can also be accessed on MDPI Journals, Microoganisms, article 1160.