Large, predatory, non‐indigenous species such as the cladoceran, Bythotrephes longimanus , can have a profound effect on aquatic food webs, but determining the prey consumed by such species is problematic because they shred prey externally and consume only soft body tissues. We assessed the usefulness of an immunochemical approach, in which putative zooplankton prey were homogenized and polyclonal antibodies against total proteins were raised in rabbits and purified against predator proteins. Using either dot‐blot or enzyme‐linked immunosorbent assay‐plate formats, assays easily detected prey proteins in single B. longimanus . Issues encountered included some degree of cross‐reaction with predator proteins and among prey species for some antisera and questions concerning determination of a correct blank value for assays, however, there are feasible approaches to resolving these issues. Immunochemical assays were readily applied in to a total of 185 individual B. longimanus in the Lake Michigan pelagic ecosystem in summer of 2008 and 2009 and indicated ingestion of cladoceran and copepod species, typically described in the literature, but also dreissenid veliger larvae and the large copepod Limnocalanus macrurus , not usually considered prey for Bythotrephes . Assays results showed some degree of correlation with numerical abundances of zooplankton prey in the water column, suggesting generalist feeding. Protein immunochemical assays offer a quick, sensitive and practical approach to examining planktonic food‐web questions that are compatible with, but have certain advantages over, alternatives such as nucleic acid techniques.

中文翻译：

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免疫化学方法识别淡水浮游动物中的猎物

大型的，掠夺性的，非本土物种，例如锁骨，Bythotrephes longimanus，可能对水生食物网产生深远影响，但是确定此类物种所消耗的猎物是有问题的，因为它们从外部切碎了猎物并且仅消耗软体组织。我们评估了一种免疫化学方法的有用性，在该方法中，将假定的浮游动物猎物进行了均质化，并针对兔子制备了针对总蛋白的多克隆抗体并针对捕食者蛋白进行了纯化。使用斑点印迹或酶联免疫吸附测定板形式，可轻松检测单个长双歧杆菌中的猎物蛋白。遇到的问题包括与捕食者蛋白质以及某些抗血清在猎物种类之间的某种程度的交叉反应，以及与测定检测方法的正确空白值有关的问题，但是，有解决这些问题的可行方法。免疫化学分析已在2008年和2009年夏季轻易地应用于密歇根湖中上层生态系统中的总共185个长双歧杆菌，表明摄入了角藻类和co足类物种，通常在文献中也有描述，但也摄入了苔藓类植物的幼虫和大型pe足类Limnocalanus macrurus，通常不被认为是Bythotrephes的猎物。化验结果表明，水柱中浮游动物的猎物数量与数量存在一定程度的相关性，表明该动物为全食动物。蛋白质免疫化学分析提供了一种快速，灵敏和实用的方法来检查浮游食物网问题，这些问题与核酸技术等替代方法兼容，但具有某些优势。