Carlos G M, Telfer S B, Johnson C L, Givens D I, Wilkins R J, Newberry R D
Department of Animal Physiology and Nutrition, University of Leeds, UK.
J Dairy Res. 1987 Nov;54(4):463-70. doi: 10.1017/s0022029900025668.
Four vitamin B12 assays were compared using blood sera from Friesian cows on winter diets or grazing. In herd 1, ten animals were blood-sampled three times at monthly intervals and the vitamin B12 concentration of the sera determined by the Poteriochromonas malhamensis and Lactobacillus delbrueckii assays. At all three sampling dates the results produced by the P. malhamensis assay were significantly greater than those produced by the L. delbrueckii assay. Cows in herd 2 were divided into two groups, each of 30 animals. One group was given a soluble glass bolus releasing cobalt and the other was unsupplemented. Milk yields were recorded throughout the experimental period and herbage samples were taken at intervals for cobalt determinations. Blood samples were taken at intervals from January to September 1983 and the vitamin B12 concentration of the sera determined by four different assay methods: the P. malhamensis and L. delbrueckii microbiological assays and the Becton Dickinson and RIA Products 'No-boil' radioassays. The last of these failed to detect vitamin B12 in any sample. There was a significant difference between the results obtained by the three other assays, with the Becton Dickinson radioassay consistently producing the lowest result and the P. malhamensis assay the highest result of the three. There was no significant effect of cobalt supplementation on milk yield.
使用来自冬季日粮饲养或放牧的弗里斯兰奶牛的血清，对四种维生素B12检测方法进行了比较。在牛群1中，10头动物每隔一个月采血3次，并通过马尔哈姆帕特里奥染色单胞菌检测法和德氏乳杆菌检测法测定血清中的维生素B12浓度。在所有三个采样日期，马尔哈姆帕特里奥染色单胞菌检测法产生的结果均显著高于德氏乳杆菌检测法产生的结果。牛群2中的奶牛被分为两组，每组30头。一组给予释放钴的可溶性玻璃丸剂，另一组不补充。在整个实验期间记录产奶量，并定期采集牧草样本进行钴含量测定。在1983年1月至9月期间定期采集血样，并通过四种不同的检测方法测定血清中的维生素B12浓度：马尔哈姆帕特里奥染色单胞菌检测法和德氏乳杆菌微生物检测法以及贝克顿·迪金森公司和RIA产品公司的“无需煮沸”放射免疫检测法。其中最后一种方法未能在任何样本中检测到维生素B12。其他三种检测方法所得结果存在显著差异，在这三种方法中，贝克顿·迪金森放射免疫检测法的结果始终最低，而马尔哈姆帕特里奥染色单胞菌检测法的结果最高。补充钴对产奶量没有显著影响。
