Arthur J R
Biochemistry Division, Rowett Research Institute, Bucksburn, Aberdeen, United Kingdom.
J Nutr. 1988 Jun;118(6):747-55. doi: 10.1093/jn/118.6.747.
In four experiments, attempts were made to induce nutritional myopathy in calves given a selenium- and vitamin E-deficient diet (less than 0.01 mg Se/kg, less than 2 mg total vitamin E/kg). In housed calves, combined selenium and vitamin E deficiency was insufficient to provoke the large increase in plasma creatine kinase activity typical of muscle damage. Such increases were only obtained when selenium- and vitamin E-deficient calves were turned out from indoor housing in small pens to open pasture. The rises in plasma creatine kinase activity on turnout were prevented when the calves had consumed diets supplemented with 0.1 mg Se/kg (as Na2SeO3). The percentage of the polyunsaturated fatty acid, linolenic acid (18:3 omega 3), in plasma total fatty acids was up to 10-fold higher in calves consuming fresh grass at pasture or indoors than in those housed indoors and fed purified diet. However, in the housed calves there were no rises in plasma creatine kinase activity, whereas large increases occurred in those turned out to pasture. Thus, because increased dietary polyunsaturated fatty acid at turnout is not the sole trigger for the development of myopathy in selenium- and vitamin E-deficient calves, additional unidentified dietary or environmental factors must also be involved.
在四项实验中，研究人员尝试对食用缺硒和维生素E日粮（硒含量低于0.01毫克/千克，总维生素E含量低于2毫克/千克）的犊牛诱发营养性肌病。在圈养的犊牛中，硒和维生素E同时缺乏不足以引发典型肌肉损伤所导致的血浆肌酸激酶活性大幅升高。只有当缺硒和维生素E的犊牛从小围栏的室内圈养转移到开阔牧场时，才会出现这种升高。当犊牛食用添加了0.1毫克硒/千克（以亚硒酸钠形式）的日粮时，转移到牧场后血浆肌酸激酶活性的升高得以预防。与在室内圈养并喂食纯化日粮的犊牛相比，在牧场或室内食用鲜草的犊牛血浆总脂肪酸中多不饱和脂肪酸亚麻酸（18:3 ω3）的百分比高出多达10倍。然而，在圈养的犊牛中，血浆肌酸激酶活性没有升高，而转移到牧场的犊牛则大幅升高。因此，由于转移到牧场时日粮中多不饱和脂肪酸增加并非缺硒和维生素E的犊牛发生肌病的唯一触发因素，必定还涉及其他未明确的日粮或环境因素。
