摘要
试验用50日龄Wistar纯系雄性大鼠39只研究了不同锌源的生物学效价。试验采用3×4因子试验设计,3种锌源为硫酸锌、赖氨酸螯合锌和蛋氨酸螯合锌。在缺锌纯合日粮基础上分别添加100、200、300、400mg/kg锌构成12种试验日粮。试验共13个处理,每处理3重复。预试期35天,大鼠自由采食缺锌纯合日粮;试验期14天,饲喂各试验日粮。试验结束时屠宰大鼠,取肝脏、肾脏、脾脏、胫骨及血清样品,用于测定肝脏、肾脏、脾脏、胫骨锌浓度和血清锌、血清碱性磷酸酶活性。试验结果表明:①在本试验条件下,日粮外加锌源对组织器官锌浓度及血清锌、血清碱性磷酸酶活性影响显著或极显著。②随日粮锌水平增加,大鼠组织器官锌浓度及血清锌、血清碱性磷酸酶活性都显著或极显著地增加。③采用斜率比法,不同判据指标得到的赖氨酸螯合锌和蛋氨酸螯合锌的相对生物学效价不同。④综合考虑本试验获得的回归方程的显著性、相关系数和日粮锌水平对各测定指标的影响,血清碱性磷酸酶活性、胫骨、肝脏、血清锌浓度可以作为适合本试验条件的评定锌源生物学效价的敏感指标。设硫酸锌为100%,赖氨酸螯合锌的相对生物学效价为141%～205%,综合平均165%。蛋氨酸螯合锌的相对生物学效价为135%～206%,综合平均165%。
An experiment was conducted with 39 fifty day-old male Wistar rats to estimate bioavailability of different zinc sources for rats. 3×4 factorial design was used in this experiment.Rats were allotted randomly to thirteen dietary treatments with three duplicates that included an purified diet based on isolated soybean protein and corn starch and glucose(Zn content 2mg/kg DM basis)or this basal diet supplemental with 100,200,300 or 400 mg/kg Zn either as ZnSO4·7H2O,Zn-Lys or Zn-Met.After having been fed zinc-deficient basal diet for 35 days,rats were fed experimental diets for 14 days.At the end of experiment,rats were killed and liver,kidney,spleen and tibia Zn content,serum Zn and alkaline phosphatase of serum were determined.The results indicated that:①Under the conditions of this experiment,Zn content in selected tissues and organs,serum Zn and alkaline phosphatase of serum were significantly affected by zinc sources.②With increasing dietary Zn level,zinc content in determined tissues and organs,serum Zn and alkaline phosphatase of serum significantly increased.③Using the slope-ratio technique from regression of common logarithm value of different indexes on mean daily Zn intake,relative bioavailability of Zn-Lys and Zn-Met were different.④Synthetically analysis of the significance of regression equation and the effect of dietary Zn on indexes determined in this experiment showed that alkaline phosphatase of serum,Zn content of tibia and liver and serum Zn were sensitive indicator.If Zn from ZnSO4·7H2O,set at 100%,the relative bioavailability values were estimated to be 141%～205% for Zn-Lys and 135%～206% for Zn-Met.Average values of Zn-Lys and Zn-Met are all 165%.
出处
《动物营养学报》
CAS
CSCD
2004年第3期20-25,共6页
CHINESE JOURNAL OF ANIMAL NUTRITION
