Extensification of the grasslands by enlargement in suckling areas in the lowlands.

摘要

Two trials have been carried out for 5-6 years at the ITCF Station at La Jailliere and at the ITCF-SUACI Station at Jeu-les-Bois, in order to study the effect of extensification (1.5 vs 1.2 mother-calf couple/ha at La Jailliere; 1.2 vs 0.9 couple/haat Jeu-les-Bois) on the pasture production, the feeding value of the herbage on offer, and the performances of the grazing suckler cows and their calves. In spite of the strong reduction in the amount of nitrogen fertilizer applied (-60 to -70%), the production level of the pastures remained satisfactory (7.1 to 8.3 t DM/ha according to the station). There were but small differences between the controls and the extensified systems as regards the feeding value of the herbage on offer, or the amounts onoffer or utilized by the animals. Lastly, a forage harvest on average 22% larger with the extensified systems made it possible to increase the stores and to give a greater autonomy to the farming systems (except for the system with 1.5 couple/ha at La Jailliere).