SEASONAL ENERGY-REQUIREMENTS OF WAPITI (CERVUS-ELAPHUS) FOR MAINTENANCE AND GROWTH

Seasonal energy intakes of 6- to 14-mo-old wapiti hinds were determine d in energy balance trials under pen and field conditions in winter, s pring and summer. Six animals grazed native pastures supplemented with alfalfa hay when pasture availability declined in winter. Another six were penned and fed alfalfa-barley pellets to maximize growth through out the year. Season and diet-specific metabolizable energy requiremen ts for maintenance and liveweight gain were determined from regression of metabolizable energy intake on gain. Daily maintenance requirement s of penned wapiti ranged from (mean +/- SE) 473 +/- 35 kJ kg -0.75 in winter to 728 +/- 78 kJ kg-0.75 in summer. On spring and summer pastu re, daily ecological maintenance requirements ranged from 900 +/- 26 t o 984 +/- 37 kJ kg-0.75. Energy requirements for gain were the same in pen and field trials, ranging from 25 +/- 6 to 33 +/- 5 kJ g-1 in win ter and from 40 +/- 6 to 43 +/- 12 kJ g-1 in spring and summer. This s tudy provides basic information on the metabolizable energy needs of w apiti and insights into how their seasonal requirements can be optimal ly met.