Gizzi Giséile, von Holst Christoph, Baeten Vincent, Berben Gilbert, van Raamsdonk Leo
European Commission, Directorate General Joint Research Centre, Institute for Reference Materials and Measurements, B-2440, Geel, Belgium.
J AOAC Int. 2004 Nov-Dec;87(6):1334-41.
An intercomparison study was conducted to determine the presence of processed animal proteins (PAPs), including meat and bone meal (MBM) from various species, in animal feed. The performances of different methods, such as microscopy, polymerase chain reaction (PCR), immunoassays, and a protocol based on iquid chromatography (LC), were compared. Laboratories were asked to analyze for PAPs from all terrestrial animals and fish (total PAPs); mammalian PAPs; ruminant PAPs; and porcine PAPs. They were free to use their method of choice. In addition, laboratories using microscopy were asked to determine the presence of PAPs from terrestrial animals, which is applicable only to microscopy. For total PAPs microscopy, LC and some immunoassays showed sufficient results at a concentration as low as 0.1% MBM in the feed. In contrast, PCR was not fit for purpose. In differentiating between MBM from terrestrial animals and fishmeal, microscopy detected 0.5% of terrestrial MBM in feed in the presence of 5% fishmeal, but was less successful when the concentration of MBM from terrestrial animals was 0.1%. The animal-specific determination of MBM from mammals or, more specifically from either ruminants or pigs, by PCR showed poor results, as indicated by a high number of false-positive and false-negative results. The only PCR method that scored quite well was applied by a member of the organizer team of the study. Immunoassays scored much better than PCR, showing sufficient sensitivity but some deficiency in terms of specificity. The results also demonstrated that the reliable determination of MBM from ruminants has not been resolved, especially for low concentrations of MBM (0.1%) in feed. Comparison of the results for mammalian MBM from all methods indicated that, for control purposes, the immunoassay method, especially when applied as dipsticks, could be used as a rapid screening method combined with microscopy to confirm the positive samples. However, implementation of such a system would require that the immunoassays were previously validated to demonstrate that this approach is fit for purpose. The determination of ruminant or porcine PAPs by immunoassays was more difficult, partly because the MBM in this study contained about 50% bovine and porcine material, thereby reducing the target concentration level to 0.05%.
开展了一项比对研究，以确定动物饲料中是否存在加工动物蛋白（PAP），包括来自各种物种的肉骨粉（MBM）。对不同方法的性能进行了比较，如显微镜检查、聚合酶链反应（PCR）、免疫测定以及基于液相色谱（LC）的方法。要求各实验室分析所有陆生动物和鱼类的PAP（总PAP）；哺乳动物PAP；反刍动物PAP；以及猪PAP。他们可以自由选择使用自己的方法。此外，要求使用显微镜检查的实验室确定陆生动物PAP的存在情况，这仅适用于显微镜检查。对于总PAP，显微镜检查、LC和一些免疫测定在饲料中MBM浓度低至0.1%时显示出足够的结果。相比之下，PCR不适用。在区分陆生动物的MBM和鱼粉时，显微镜检查在存在5%鱼粉的情况下检测到饲料中0.5%的陆生MBM，但当陆生动物的MBM浓度为0.1%时，效果较差。通过PCR对哺乳动物或更具体地说反刍动物或猪的MBM进行动物特异性测定，结果不佳，假阳性和假阴性结果数量较多表明了这一点。得分相当不错的唯一PCR方法是由该研究的组织者团队成员应用的。免疫测定的得分比PCR好得多，显示出足够的灵敏度，但在特异性方面存在一些不足。结果还表明，反刍动物MBM的可靠测定尚未解决，特别是对于饲料中低浓度的MBM（0.1%）。所有方法对哺乳动物MBM结果的比较表明，出于控制目的，免疫测定方法，特别是用作试纸条时，可作为一种快速筛查方法，与显微镜检查相结合以确认阳性样品。然而，实施这样一个系统需要预先验证免疫测定，以证明这种方法是适用的。通过免疫测定确定反刍动物或猪的PAP更困难，部分原因是本研究中的MBM含有约50%的牛和猪材料，从而将目标浓度水平降低到了0.05%。
