대두박(大豆粕)의 처리방법과 요소첨가 수준이 반추위 미생물 단백질합성 및 영양소 소화율에 미치는 영향 : II. 면양 대사실험(代謝實驗)에 의한 연구 II. A Study by Metabolism = Effects of Urea Levels and Soybean Meal Treatment on the Rumen Microbial Protein Synthesis and Nutrient Digestibilities

국문 초록 (Abstract)

本 實驗은 反芻家畜의 主要 植物性 蛋白質 飼料인 大豆粕을 無處理, 高壓蒸氣處理 및 乾熱處理하여 反蛋胃內의 蛋白質 分解率을 각각 80.26, 74.28 및 60.38%로 低下시킴으로서 過多한 ammonia의 發生을 抑制하고 徵生物蛋白質 合成에 必要한 부족된 nitrogen은 非蛋白態 窒素化合物인 尿素로 代贊 供給하여 飼料 蛋白質을 절약하고 그 利用性을 증진시키는데 目的이 있다. 따라서 本 硏究는 면양 代謝試驗을 통하여 同窒素價로 大豆粕 蛋白質源의 一部를 尿素로 0, 1, 2및 3% 代潛하였을때 大豆粕 蛋白質 分解率에 따른 NH₃-N 利用性과 微生物 蛋白質 合成量의 變化 및 揮發性 脂肪酸 生成 등을 測定하였으며 實驗結果를 要約하면 다음과 같다.
1. 反芻胃液 100㎖당 평균 NH₃-N 濃度(㎎)는 0, 1, 2, 3% 代贊時 各 處理區別 공히 尿素代贊率이 增加할수록 NH₃-N 濃度가 높아지는 傾向이었으나 處理區間에 有意性은 없었다(P>0.05).
2. 窒素 蓄積率(%)은 尿素 0, 1, 2, 3% 代贊時에 尿素 代贊率이 높을수록 減小하였으며 乾熱處理 大豆粕區가 가장 높은 傾向을 나타냈으나 다른 處理區와 有意性은 없었다(P>0.05).
3. 反芻胃液 100㎖당 평균 徵生物 건물 합성량(g)은 尿素 0, 1, 2, 3% 代贊時 尿素 代贊 水準別로는 큰 差異가 없었으며 蛋白質 分解率이 떨어질수록 感小하는 傾向이었으나 有意性은 없었다(P>0.05).
4. 反芻胃液 100㎖당 평균 徵生物 건물 합성량(㎎)은 尿素 0, 1, 2, 3% 代贊시 蛋白質分解率이 떨어질수록 徵生物 蛋白質 生産量이 減小하는 傾向을 나타냈으며 處理區 間에는 尿素 1% 水準(P<0.01)과 2% 水準(P<0.05)에서 有意性이 認定되었다.
5. 反芻胃液 ℓ당 평균 總 揮發性 脂肪酸 生成量(mM)은 尿素 0, 1, 2, 3% 代贊時 尿素를 代贊하지 않았을때 높은 生成量을 나타냈으나 각 處理區間에 일정한 傾向은 없었다.

다국어 초록 (Multilingual Abstract)

Effects of urea levels(0, 1, 2 and 3%) and soybean meal treatment digestibilities on the rumen microbial protein synthesis, VFA production and nutrient utilization were studied using metabolism trial with fistulated 4 rams. Treatment groups were commercial solvent-extracted untreated soybean meal(USBM), autoclaved soybean meal(ASBM) and dry heated soybean meal(DSBM), respectively. Degradabilities of soybean meals 80.3, 74.2 and 60.4% for USBM, ASBM and DSBM, respectively.
The results which were obtained from this study are summarized as follows:
1. The average NH₃-N concentrations (㎎/100㎖) were increased as increasing urea levels and were lower in DSBM than the USBM and ASBM.
2. Nitrogen retention rates(%) in vivo, were decreased as increasing urea levels and were highest in DSBM than USBM and ASBM.
3. The average microbial dry matter yields(g/100㎖) were not different among urea levels, but decreased as decreasing protein degradabilities.
4. The average microbial protein yields(㎎/100㎖) were higher in USBM which was high degradability than DSBM and ASBM.
5. The average total VFA productions(mM/ℓ) were the highest in 0% urea level in all treatment groups and were higher in USBM and DSBM than ASBM.