Pre-weaning growth response of lambs fed creep mixtures with varying levels of energy and protein

The pre-weaning nutrient requirements for growth of lambs were assessed by feeding them on ad libitum creep mixtures with free suckling and free choic e of Pala (Z. nummularia) leaves. Thirty six lambs (15 days old) were divid ed into three equal groups and fed creep mixtures containing high (HEHP), m edium (MEMP) and low (LELP) levels of digestible energy and protein. A cafe teria system of feeding management was used. The ratio of creep mixture. pa la leaf and milk in the total DMI of HEHP lambs was 74.9: 11.4:13.7. The co rresponding ratios in DMI were 73.8:14.3:11.8 and 90.3:2.1:7.6 in MEMP and LELP regimens. Digestibility of DM. OM and CP was higher (P < 0.01) in HEHP than MEMP and LELP. Digestibility of NDF and ADF was also significantly (P < 0.01) higher in HEHP than MEMP and LELP. However. digestibility of cellu lose and hemicellulose were higher (P < 0.01) in LELP than other two groups . The lambs in all the three groups were in positive N balance while per ce nt N retention was lower (P < 0.01) in LELP (52.6%) compared to MEMP (61.5% ) and HEHP (70.4%). The lambs in HEHP, MEMP and LELP consumed 58.2, 51.6 an d 83.5 g DM, 10.4, 7.4 and 8.0 g DCP and 250.4, 163.2 and 228.9 kcal DE/kg W-0.75/day amounting to an average of 43 g DCP/Mcal DE consumed/day and had 124, 108 and 124 g ADG, respectively It is concluded from the study that a d libitum LELP creep mixture with free suckling and free choice pala (Z. nu mmularia) leaves was adequate to meet the growth requirement for 124 g pre- weaning average daily gain. (C) 2001 Elsevier Science B.V. All rights reser ved.