Ganho compensatório em cordeiras na fase de recria: Desempenho e medidas biométricas

Abstract

The objective of this trial was to evaluate the compensatory growth and biometrical measurements on lambs feed restricted or ad libitum fed. In the first of two periods of 60 days, 18 7/8 Ile de France x 1/8 Ideal female lambs were assigned to three treatments in a completely randomized design as follows: 1) no feed restriction (ad libitum fed), 2) 30% of feed restriction or 3) 60% of feed restriction calculated as proportion of the ad libitum fed group intake. In the second period, all animals were ad libitum fed. At the end of the first period, lambs with no feed restriction and those with 30% of feed restriction gained 18 and 0.8% of body weight (BW), respectively, compared to their initial weight while lambs with 60% of feed restriction lost 15% of BW. In the second period, BW gain was greatest on animals with 30% of feed restriction (196.24 g/d), lowest on those not feed restricted (116.20 g/d) and intermediate on animals with 60% of feed restriction. Feed conversion was of 10.09 and of 5.97 on lambs not feed restricted and with 30% of feed restriction, respectively. The biometrical measurements were similar at the beginning of the trial but at the end of the first period there were reductions of 16% on shoulder width, 21% on hip width, 6.9% on chest girth, and 39% on body condition in animals with 60% of feed restriction. Feed restriction of 60% also reduced DM intake and final BW of lambs, which compromised most of the biometrical measurements. On the other hand, 30% of feed restriction can be an alternative feeding management because of the observed improvement in feed conversion and decreased total feed intake. © 2007 Sociedade Brasileira de Zootecnia.