Influence of Livestock System on Growth Performance of Growing Churra Tensina Lambs

The objective was to study the influence of livestock production system, extensive vs. intensive, on growth performance of lambs of Churra Tensina breed. In the extensive system, 18 lambs were reared with their ewes on pasture from 7 days old to slaughter, with no supplementation feed. The intensive system, 18 lambs were kept indoor with free access to concentrate, while their ewes were also indoor from 17 h to 8 h, receiving 500 g of barley as concentrate and the rest of time were given access to a pasture. At 50 days old, lambs from intensive treatment were weaned. When lambs had a liveweight of 22-24 kg were slaughtered. Lambs were weighted once a week and diet intake was controlled weekly. The lamb weights at birth, at 52 days old (weaning for intensive treatment) and at slaughter were not affected by treatment (P>0.05). However the time spent from birth to slaughter was greater in extensive treatment with 85 days, while intensive lambs only needed 74 days (P<0.01). The average daily gain was higher for intensive treatment with 281 g/day than 242 g/day in extensive. This higher performance of intensive treatment was consequence of the supplementation of 26 kg of barley/ewe and 39.3 kg of concentrate/lamb, while the extensive treatment did not received any supplementation.