02556naa a2200277 a 450000100080000000500110000800800410001902400550006010000150011524501370013026000090026752017410027665000180201765000100203565000250204565000230207065000100209365000130210365000160211665000140213265000100214665300220215665300180217870000170219677300650221315241642023-07-21       1999    bl uuuu     u00u1 u    #d7 ahttps://doi.org/10.1016/S0921-4488(99)00005-X2DOI1 aSANTRA, A.  aEffect of protein levels in creep mixture on nutrient utilization and growth performance of pre-weaner lambs.h[electronic resource]  c1999  aAbstract: The pre-weaning protein requirement for growing lambs was assessed in hot semi-arid environment by maintaining them on ad libitum creep mixture having 18% (G1), 22% (G2) and 27% (G3) CP in addition to free suckling and free choice cowpea hay. Birth weight of males was higher (p &lt 0.05) than the female lambs whereas it was similar in the treatments. The finishing body weight of lambs in pre-weaning phase (60 days of age) was also similar in the three groups (11.3 kg) with total gain of 7.4 kg and average daily gain of 140 g. Males were heavier than female lambs at weaning stage irrespective of the treatments. Feed conversion efficiency was similar in the groups requiring 3.3 to 3.5 kg DM for each kg gain in body weight. Male lambs had better feed conversion efficiency than females. Digestible crude protein (DCP) intake/kg gain was higher (p &lt 0.01) in G3 than G2 and G1 whereas TDN intake/kg gain was similar in these groups. Digestibility of DM, OM, NDF, ADF and cellulose was similar in these groups while digestibility of CP and EE was lower in G1 than G2 and G3. Lambs in all three groups were in positive nitrogen balance whereas percent nitrogen retention was lower in G3 than G2 and G1 due to higher faecal and urinary losses. Lambs in G1, G2 and G3 consumed 82.2, 83.6 and 83.0 g DM, 9.1, 11.9 and 15.1 g DCP and 46.8, 48.8 and 49.6 g TDN/kg W0.75/day and had 140, 139 and 142 g average daily gain, respectively. It is concluded that higher levels of dietary protein with similar energy content in the creep mixture was wasted in faeces and urine and that 18% CP in ad libitum creep mixture with free suckling and free choice cowpea hay was adequate for pre-weaner lambs under hot semi-arid environment.  aAnimal growth  aLambs  aNutrient utilization  aRuminant nutrition  aSheep  aCordeiro  aCrescimento  aNutriente  aOvino  aNivel de proteina  aProtein level1 aKARIM, S. A.  tSmall Ruminant Researchgv. 33, n. 2, p. 131-136, Jul. 1999.