Bergner H, Schwandt H
Institut für Ernährungsphysiologie, Humboldt-Universität zu Berlin.
Arch Tierernahr. 1991 Oct;41(7-8):675-90. doi: 10.1080/17450399109428512.
Wistar rats of a live weight of about 100 g were divided into 14 groups (5 animals/group). The rations given supplied the animals with 75%, 100% and 125% lysine, which brought about a moderate growth of the animals of approximately 2 g/animal and day achieved by limited feeding. The 3 lysine levels mentioned could be achieved by lysine supplements (L-lysine-HCl) for the following rations: barley (B), wheat (W), and wheat gluten (WG). For isolated soybean protein (assay protein) (S) the lysine levels 100% and 125% and for soybean meal (SM) the levels 116% and 125% could only be achieved. A control group with whole egg ration (W) (with its natural lysine content of 125% of the requirement) were also tested as comparison. During the 10-day period of the main experiment all 14 rations were supplemented with 0.5 g 15N-lysine (alpha amino group, 95% labelled with 15N). The N balance could only be significantly improved by lysine supplements in the rations B, W and SM with the lysine level of 125%. The biologic value of the protein sources was in rations B and WG also significantly improved by the highest lysine supplement. 15N excess (15N') from the deaminated 15N lysine was excreted with diet B rich in crude fibre mainly in faeces (more than 15% of the intake) and only about 10% in urine. With the diets without native crude fibre the excretion quota changed in favour of urine. The following 15N' amounts in per cent of 15N' intake from lysine were excreted in urine and faeces: B 75 = 31.3, B 100 = 30.9, B 125 = 28.0, W 75 = 24.3, W 100 = 32.2, W 125 = 32.6, GW 75 = 18.3, WG 100 = 24.2, WG 125 = 28.1, S 100 = 39.4, S 125 = 50.4, SM 116 = 34.9, SM 125 = 32.9, W 125 = 19.1. 15N excretion in urine and faeces increased in comparable relations in 6 cases of lysine increase levels only. Gross utilization of lysine can only conditionally be quantified by 15N labelled lysine supplement.
将体重约100克的Wistar大鼠分为14组（每组5只动物）。所提供的日粮为动物提供75%、100%和125%的赖氨酸，通过限量饲喂使动物实现约2克/只/天的适度生长。上述3种赖氨酸水平可通过以下日粮添加赖氨酸补充剂（L-赖氨酸盐酸盐）来实现：大麦（B）、小麦（W）和小麦面筋（WG）。对于分离大豆蛋白（测定蛋白）（S），只能实现100%和125%的赖氨酸水平，对于豆粕（SM），只能实现116%和125%的水平。还测试了一组以全蛋日粮（W）（天然赖氨酸含量为需求量的125%）作为对照进行比较。在主要实验的10天期间，所有14种日粮均添加0.5克15N-赖氨酸（α-氨基，95%用15N标记）。只有当赖氨酸水平为125%时，在日粮B、W和SM中添加赖氨酸才能显著改善氮平衡。最高赖氨酸补充剂也显著提高了日粮B和WG中蛋白质来源的生物学价值。来自脱氨基15N赖氨酸的15N过量（15N'），在富含粗纤维的日粮B中，主要通过粪便排出（超过摄入量的15%），通过尿液排出的仅约为10%。对于不含天然粗纤维的日粮，排泄比例有利于尿液。以下是尿液和粪便中排出的15N'占赖氨酸摄入15N'的百分比：B 75 = 31.3，B 100 = 30.9，B 125 = 28.0，W 75 = 24.3，W 100 = 32.2，W 125 = 32.6，GW 75 = 18.3，WG 100 = 24.2，WG 125 = 28.1，S 100 = 39.4，S 125 = 50.4，SM 116 = 34.9，SM 125 = 32.9，W 125 = 19.1。仅在6种赖氨酸增加水平的情况下，尿液和粪便中的15N排泄量以可比关系增加。赖氨酸的总利用率只能通过15N标记的赖氨酸补充剂有条件地进行量化。
