Tannins are bioactive phenolic compounds widely distributed in
plant kingdom, which interfere with protein and lipid metabolism
in the rumen, by forming undegradable complexes with feed
proteins and by modulating the biohydrogenation (BH) of polyunsaturated
fatty acids (PUFA; Buccioni et al., 2012; Minieri et al.,
2014). Tannins may differ in their solubility and other chemical
and physical characteristics, and also differ in their capacity to bind
feed proteins or to influence the activity of rumen microorganisms