Nutritive value and fatty acid profile of birdsfoot trefoil (Lotus corniculatus) and white clover (Trifolium repens) in Alpine pastures.

A survey was conducted over the summer of 2014 on nine Alpine pastures located in NW Italy. The aim was to characterize two wild legumes: Lotus corniculatus (LC) and Trifolium repens (TR). Collected samples were analysed for chemical, fatty acid (FA) profile and in vitro digestibility. The values of dry matter (DM), neutral detergent fibre (NDF), lignin and gross energy (GE) in LC samples comply with literature, while values of crude protein (CP, 156 g/kg) and lipid (17.6 g/kg) are lower, and values of acid detergent fibre (ADF, 418 g/kg) are higher than those of cultivated LC. For TR, values of DM, lignin and GE comply with ranges, while values of CP (152 g/kg) and lipid (16.3 g/kg) are lower, and values of NDF (534 g/kg) and ADF (357 g/kg) are higher than those of cultivated TR. Digestibility of LC was lower than TR, but less variable. Averages values of 710, 417, 205 and 284 g/kg of DM were obtained in LC for in vitro true digestibility (IVTD), in vitro NDF digestibility (NDFD), in vitro digestible NDF (dNDF) and indigestible NDF (iNDF), respectively. The same parameters for TR were 781, 589, 314, 220 g/kg of DM for IVTD, NDFD, dNDF and iNDF, respectively. LC and TR were characterized by a high proportion of ?-linolenic acid (ALA) which ranged from 312 to 521 and from 347 to 525 g/kg of total FA, respectively. Mean values of linoleic and palmitic acid were 71 and 82 g/kg of total FA in the LC and 123 and 90 g/kg of total FA in the TR, respectively. In conclusion, LC and TP are an important source of ALA and other unsaturated FA, present a high content of CP and a good IVTD, and their presence improves the feed quality of the alpine pastures.