Tannins are plant secondary compounds known to enhance the efficiency of energy and protein use during rumen fermentation (Lagrange et al., 2020) reducing rumen methanogenesis and altering N partitioning (Jayanegara et al. 2012, Lagrange et al., 2020). However, there is still a large variation in fermentation outcomes and gas production dynamics in response to supplementation of tanniniferous plants which have been performed in short-duration experiments that typically range between ~ 20-40 d.
The duration of these experiments is to target the immediate adaptation of the ruminal microbiome and animal parameters in response to tannin administration. However, a detailed evaluation of rumen microbial adaptation to tannins in cattle has not yet occurred.
We hypothesise that the administration of tannins to lactating dairy cows will reduce methanogenic archaea populations in the rumen reducing methane production and altering the patterns of VFA production (Marshall et al., 2022). We also hypothesise that cows eating tannins will be supplied with more antioxidants that contribute to reducing oxidative stress.
