Valorisation par des bovins ou des ovins de pelouses et de landes subalpines des Alpes françaises

Utilization by cattle or by sheep of sub-alpine rough grazings in the french Alps

The "Institut National d'Etudes Rurales et Montagnardes" has been studying for five years the evolution of the vegetation in two Alpine sward types (short grass pasture with Festuca paniculata and heath-land with Vaccinium myrtillus and V. uliginosum), grazed by cattle or by sheep ; the animal performances have also been recorded. Observations were made at two levels : four experimental plots (2-3 ha) and the Alpine pastures at their true scale. The stocking rate is high (9 ewes/ ha and 1 heifer/ha), and the turning to grass takes place early.The results obtained with dairy heifers or young beef cattle are moderate, but satisfactory if the animals are well fed during the Winter (heifers) or finished off indoors. The Iive-weight gains of the sheep are comparable to those of the cattle (about 60 kg/ha). but in both cases the individual performances decrease from year to year, owing to a succession of dry Summers and the maintenance of a high stocking-rate.Sheep and cattle have induced different floristic evolutions during these 5 years. Under cattle grazing, Festuca paniculata and Nardus stricta regress sharply after a very dry Summer, and are replaced by legumes and rosette species. Under sheep grazing, there is a slight decrease of Festuca rubra and of the pastoral value. Alternating  the animal species should be contemplated.