반추가축영양 : 절식대사 시험에 의한 한우 수소의 유지에너지 요구량 결정에 관한 연구 = Ruminant Nutrition : Energy Requirements of Growing Hanwoo Bulls for Maintenance by Fasting Metabolism

다국어 초록 (Multilingual Abstract)

Net and metabolizable energy requirements for maintenance of Hanwoo (Korean native cattle) bulls were estimated in twenty-eight fasting metabolism trials using seven different feeds at four stages of body weight(100, 200, 300 and 400㎏). Three cattle for each of twenty-eight trials fed at a level of maintenance energy requirement were housed in metabolic stalls during the 5 days of collection period. Thereafter, during the 2 days of respiration period the heat production was measured by indirect calorimetry using respiratory chamber. After finishing the respiratory metabolism trials under the maintenance level, experimental animals were fasted for 5 days and were measured heat production by indirect calorimetry using respiratory chamber. Seven different fees were: 1) mixed ration of concentrate and rice straw, 2) mixed ration of concentrate and mixed grass hay, 3) mixed ration of concentrate and corn silage, 4) rice straw alone, 5) mixed grass hay alone, 6) corn silage alone, 7) concentrate alone. Fasting heat production were 66.05/W^0.75 at 100㎏ of body weight and 60~63㎉/W^0.75 at 200~400㎏ of body weight. When subtracting heat loss by muscular work from the fasting heat production, basal metabolic rate was 55.92㎉/W^0.75. The average values of NEm requirements were obtained by adding urinary energy excretion to the basal metabolic rates were 69.1, 62.1, 65.8 and 64.4㎉/W^0.75 for the four stages of body weight, respectively. The ME requirement for maintenance could be calculated using retained energy and the efficiency of utilization of ME for net energy. The ME requirement for maintenance thus obtained was 102.69㎉/W^0.75.