The assessment of the nutritional value of plants rich in condensed tannins (CT) stems from the models predicting the normal nutritional value. In order to verify the effects, this study compares the nutritional value of chicory (cychorium intybus), sainfoin (onobrychis viciifolia) and lotus (lotus corniculatus) obtained with data determined using animals (in vivo, in sacco) or with prediction equations with regard to levels of CT. The organic matter digestibility (OMD) in vivo of chicory (78.8 %) was higher (p < 0.01) than the similar OMD of the two other plants (69.3 %). Sainfoin with the highest concentration of CT obtains the lowest content in digestible nitrogenous matter (DNM) with 58.7 % (vs. chicory with 69.7 and lotus with 76.5 % p<0.01). The degradability of the nitrogenous matter of plants with low CT values is comparable for chicory and lotus (64.2 % and 65.1 %) but is different to that of sainfoin 47.8 % (p < 0.01).The best forecasts for forage studied were obtained for chicory (1st cycle stage leaves without stalks) with OMD equations for a mixture with a high degree of other plants with thin leaves, for lotus (3rd cycle start of flowering) with that for legumes and for sainfoin (1st cycle start of flowering) with that for an unspecified mixture.
Determined and estimated nutritive value of chicory, birdsfoot trefoil and sainfoin