Grazing behaviour and performances of Pirenaica and Brown Swiss heifers

摘要

Grazing behaviour and performance of ten Brown Swiss and ten Pirenaica 15-month-old heifers, with pretrial weights of 327 (11.3) and 325 (8,8) kg respectively, were compared. The study was carried out at the Bescos de la Garcipollera research station(altitude 900 m), in the Spanish Pyrenees. By mid-May they were transferred to the experimental areas and allowed to graze on a natural prairie (37% P, pratensis, 26% F. arundinacea, 20 % T. repens, etc.) for 50 days. Herbage availability decreased from3170 kg DM/ha (16.1 % DM, 81.3 % digestibility) at the beginning to 1130 kg DM/ha (46.4 % DM, 55.5 % digestibility, 65.9 % dead material) at the end of the experiment.