Utilisation of the metabolisable energy of ewe's milk by the lamb

摘要

Abstract Efficiency of utilisation of ewe's milk by the lamb was studied. The comparative slaughter method was used to determine gain or loss in body fat, protein, and energy. Of 24 crossbred lambs used, 12 comprised an initial slaughter group|the remaining 12 were given ewe's milk for 21 days at four different levels of energy intake ranging from sub-maintenance to ad libitum. Lambs fed at the lowest plane of nutrition mobilised body fat and were in negative energy balance; all the others were in positive energy balance. The mean digestibility of ewe's milk was 98.4% and was unaffected by the plane of nutrition. The mean metabolisability of the diet was 95.6% for lambs in positive energy balance and 91.8% for those in negative energy balance. The metabolisable energy requirement for zero energy gain was 145.2 kcal/kg0.75 24 hr, and the efficiency of utilisation of metabolisable energy for maintenance and growth was 76.9%.