He M L, Wang Y Z, Xu Z R, Chen M L, Rambeck W A
Institut für Physiologie, Physiologische Chemie und Tierernährung, Ludwig-Maximilians-Universität, Munich, Germany.
J Anim Physiol Anim Nutr (Berl). 2003 Jun;87(5-6):229-35. doi: 10.1046/j.1439-0396.2003.00432.x.
Rare earth elements (REE) have been shown to influence growth performance in animal production, especially in pigs. In the present study, the effect of oral administration of rare earth elements on growing rats was investigated. Pure LaCl3 or an REE mixture containing 38% of LaCl3, 52% of CeCl3, 3% of PrCl3 and 7% of chlorides of other REE were used at two different concentrations as supplements to the diets. Fifty male Wistar rats at 4 weeks of age were allotted to five experimental groups: a control group; a La-low group and a La-high group with 75 and 150 mg/kg LaCl3.6H2O, respectively; a REE-low and an REE-high group with 75 and 150 mg/kg REE mixture, respectively. The animals were housed in individual pens. Feed and water were provided ad libitum. After 18 days the oral supplementation of LaCl3.6H2O or of the REE mixture improved daily body weight gain (BWG) by up to 5 or 9% (p > 0.05), respectively. LaCl3.6H2O as well as the REE mixture had positive effects (p < 0.05) on feed conversion ratio (FCR) with a decreased ratio by up to 8 and 11%, respectively. Supplementation of REE also had clear effects on blood serum parameters. The activities of alkaline phosphatase (AP) and alanine amino transferase (ALT) increased significantly (p < 0.05). At the same time, blood glucose level decreased and blood creatine level increased significantly (p < 0.05). There was no significant difference in cholesterol, total protein, albumin and urea nitrogen among the groups. There was no significant difference in triglyceride level between the control and those REE groups, however, a significantly lower (p < 0.01) triglyceride level was found in the 150 mg/kg REE mixture group compared with that in 75 mg/kg REE mixture group and the 150 mg/kg LaCl3.6H2O group. The results suggest that oral supplementation of REE improves growth performance in rats as in pigs. In this respect, concentration and type of REE supplemented to the diets are two important factors herein.
稀土元素（REE）已被证明会影响动物生产中的生长性能，尤其是在猪身上。在本研究中，研究了口服稀土元素对生长大鼠的影响。使用纯LaCl₃或含有38%LaCl₃、52%CeCl₃、3%PrCl₃和7%其他稀土氯化物的稀土混合物，以两种不同浓度作为日粮补充剂。将50只4周龄的雄性Wistar大鼠分配到五个实验组：一个对照组；一个低剂量La组和一个高剂量La组，分别含有75和150mg/kg LaCl₃·6H₂O；一个低剂量REE组和一个高剂量REE组，分别含有75和150mg/kg稀土混合物。动物单独饲养在笼子里。自由提供饲料和水。18天后，口服补充LaCl₃·6H₂O或稀土混合物分别使日体重增加（BWG）提高了5%或9%（p>0.05）。LaCl₃·6H₂O以及稀土混合物对饲料转化率（FCR）有积极影响（p<0.05），比例分别降低了8%和11%。补充稀土元素对血清参数也有明显影响。碱性磷酸酶（AP）和丙氨酸氨基转移酶（ALT）的活性显著增加（p<0.05）。同时，血糖水平降低，血肌酐水平显著升高（p<0.05）。各组之间胆固醇、总蛋白、白蛋白和尿素氮没有显著差异。对照组与稀土元素组之间甘油三酯水平没有显著差异，然而，与75mg/kg稀土混合物组和150mg/kg LaCl₃·6H₂O组相比，150mg/kg稀土混合物组的甘油三酯水平显著降低（p<0.01）。结果表明，口服补充稀土元素与在猪身上一样能提高大鼠的生长性能。在这方面，日粮中补充的稀土元素浓度和类型是两个重要因素。
