The purpose of this study was to use routine morphologic-based staining techniques to examine the histology of commercially labeled rawhide and rawhide-free dog chew products and compare the results to the product labeling. Ten dog chew products were examined by light microscopy using hematoxylin and eosin and Masson's trichrome stains. The products were labeled by the manufacturer as rawhide, beef hide, beef chew/rawhide free, and rawhide free. Four of the products were composed of two separate materials, a main chew roll and a second substance (filler) which was coated on or between the layers of the main chew roll. These materials were processed independently. Microscopically, a variety of tissues and materials were identified including collagen, skeletal muscle, fat, plant material, and starch. The products and their fillers were separated into four distinct groups based on microscopic appearance. The components identified in eight of the products appeared consistent with the product labeling. Two products labeled as rawhide free appeared similar to the dermis and this was inconsistent with product labeling. Masson's trichrome stain was not helpful in distinguishing tissue types in the tested products and this may have been due to the heat processing the products underwent during manufacturing. Bacteria and/or fungi were identified by microscopy in the H&E stained sections in four rawhide-free products.

中文翻译：

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狗咀嚼物的显微镜检查：组织学发现与产品标签的相关性

本研究的目的是使用常规的基于形态学的染色技术来检查商业标记的生皮和无生皮狗咀嚼产品的组织学，并将结果与​​产品标签进行比较。使用苏木精和伊红以及马森三色染色通过光学显微镜检查十种狗咀嚼产品。产品由制造商标记为生皮、牛肉皮、牛肉咀嚼物/不含生皮和不含生皮。四种产品由两种单独的材料组成，主咀嚼卷和涂覆在主咀嚼卷的层上或之间的第二物质（填料）。这些材料是独立加工的。在显微镜下，鉴定了多种组织和材料，包括胶原蛋白、骨骼肌、脂肪、植物材料和淀粉。根据微观外观将产品及其填料分为四个不同的组。八种产品中确定的成分似乎与产品标签一致。两种标记为无生皮的产品看起来与真皮相似，这与产品标签不一致。马森三色染色对区分受试产品中的组织类型没有帮助，这可能是由于产品在制造过程中经历的热处理造成的。细菌和/或真菌在四种无生皮产品的 H&E 染色切片中通过显微镜识别。两种标记为无生皮的产品看起来与真皮相似，这与产品标签不一致。马森三色染色对区分受试产品中的组织类型没有帮助，这可能是由于产品在制造过程中经历的热处理造成的。细菌和/或真菌在四种无生皮产品的 H&E 染色切片中通过显微镜识别。两种标记为无生皮的产品看起来与真皮相似，这与产品标签不一致。马森三色染色对区分受试产品中的组织类型没有帮助，这可能是由于产品在制造过程中经历的热处理造成的。细菌和/或真菌在四种无生皮产品的 H&E 染色切片中通过显微镜识别。