IN-LINE ROTATIONAL GRAZING SYSTEM (LEADERS AND FOLLOWERS) - PRODUCTIVE PERFORMANCE

The growth and fattening of 178 calves and 109 Holstein yearlings were studied in three consecutive cycles of 353 days each: A) the in line rotationg grazing system with leader calves and yearlings (followers) versus a conventional rotational system with animal categories in inde pendent grasslands, B) calves rotating in a grassland and C) yearlings rotating in another grassland. All the calves and weighed from 100 to 130 and 240 to 260 kg and were 55 to 8 and 14 to 16 months of age, re spectively. Fourteen leaders and seven followers rotated in grassland A. The leaders reaching the initial live weight of followers were slau ghtered and the remaining animals became followers, new calves were en tered with similar initial live weights so as to start another cycle. In the rainy period the animals had access to pasture and in the dry s eason a moderate protein-energy supplementation was used. Pasture and faeces samples were taken for the chemical and parasitological analyse s respectively. on account of parasites, 21.4% of the calves were cull ed in the traditional grazing system (B) due to gastrointestinal paras ites. No leader was culled because of this. Live weight gain was 545, 413 and 509 kg/ha/year for the A, B and C systems, respectively. Indiv idual live weight gain was 401, 503, 294 and 607 g/animal./day for the leaders, followers and calves under the B grazing system and yearling s under the C grazing system, respectively. Pasture availability and n utritive value was higher in the leaders. Results show that in line gr azing with leader calves rotating in front of:the yearlings (followers ) reduced gastrointestinal parasites, prevented deaths and increased l ive weight gain/ha/year compared to the traditional grazing system (B) .