Abstract
This study was conducted to compare the chemical composition, dry matter digestibility (DMD), dry matter intake, and utilization of nitrogen and energy of dairy goats (Saanen), when fed on imported timothy hay (IT), mixture grass hay (MG) and native grass hay (NG), respectively. The experimental trials were conducted from April, 2008 to December, 2008 at the environmental controlled barn of Chungnam National University. Twelve dairy goats (Saanen) were selected which had nearly the same body weight (24.2kg, male). The content of crude protein (CP) of MG hay was higher than that of other diets (p<0.05), but the contents of NDF, ADF, cellulose and lignin of IT and NG diet were higher than those of MG diet (p<0.05). The voluntary DM intake of dairy goats fed with herbage from MG diet (30.7/$BW_{kg}$/day) was higher than that of other diets, but no significant difference was observed between that of IT diet and NG diet (p>0.05). The DMD of MG diet (69.8%) was higher than that of NG diet (62.2%) and IT diet (60.8%) (p<0.05), but no significant difference was observed between that of IT diet and NG diet (p>0.05). In nitrogen utilization, the apparently digested N %, retained % and biological value of dairy goats fed with herbage from MG diet were higher and TG diet was lower (p<0.05). In energy utilization, digestible energy and the energy of apparently digested minus urinary losses of MG diet were higher than those of IT diet and NG diet (p<0.05), but no significant difference was found between IT diet and NG diet (p>0.05). Based on the results, the dry matter intake, DMD and utilization of nitrogen and energy of dairy goats of MG were higher than those of IT diet and NG diet (p<0.05), the DMD and biological value (%) of NG diet was higher than that of IT diet (p<0.05).
본 연구는 2008년 4월부터 12월까지 충남대학교 생명과학대학 내 부속 환경조절축사에서 수행하였다. 공시된 건초는 수입 Timothy 건초(수입건초), 혼합목건초 (목건초) 및 혼합 야건초(야건초)의 3처리이며 공시가축은 유 산양 (Saanen종, 평균체중 24.2 kg, male) 12두로 화학적 성분, 건물소화율, 건물섭취량과 질소 및 에너지이용성을 비교 분석하였다. 조단백질 함량은 목건초가 야건초나 수입건초에 비하여 높은 결과를 나타내었으나(p<0.05), NDF, ADF, cellulose 및 lignin 함량은 반대로 수입건초와 야건초가 높았다 (p<0.05). 건물 섭취량은 목건초 (30.7 g/BWkg)가 야건초 (24.6 g/BWkg)와 수입건초 (24.4g/BWkg)에 높은 결과를 보였으나 (p<0.05), 야건초와 수입건초 간에 유의적인 차이는 없었다. 건물소화율은 목건초가 69.8%로 야건초(62.2%)와 수입건초 (60.8%)에 높은 결과를 보였다 (p<0.05). 그러나 야건초와 수입건초간에 건물소화율의 유의적인 차이는 없었다. 외관상 생물가는 목건초가 56.0%으로 야건초 (49.2%), 수입건초 (47.7%) 순으로 나타났다 (p<0.05). 외관상 대사에너지 축적률은 목건초가 63.4%로 야건초 (54.4%)나 수입건초 (53.6%)에 비하여 높은 결과를 보였으나 (p<0.05), 역시 야건초와 수입건초 간에 유의적인 차이는 없었다. 이상의 결과로 보아, 유 산양에 의한 건물섭취량, 건물소화율과 질소 및 에너지의 이용성은 목건초가 가장 높았으며, 야건초는 수입건초에 비하여 건물소화율과 외관상 생물가가 높은 것으로 나타났다.
