Department of Animal Sciences, University of Illinois, Urbana 61801, USA.
J Anim Sci. 2012 Dec;90(12):4355-61. doi: 10.2527/jas.2012-5333. Epub 2012 Oct 16.
Chews are an important part of the pet product industry, with many having potential to decrease plaque or calculus formation. However, their digestion characteristics and gut transit time are virtually unknown. Two experiments were conducted to determine in vitro DM digestibility of expanded pork skin chews and rawhide chews, and apparent total tract digestibility (ATTD), gastrointestinal transit time, and blood metabolite measurements in healthy adult dogs fed a weight-control commercial diet and expanded pork skin chews. In Exp.1, an in vitro method that simulated gastric and small intestinal digestion was used to determine DM digestibility of expanded pork skin chews and rawhide chews. In Exp. 2, after a 22-d baseline phase, 10 purpose-bred, intact female dogs (5 to 5.5 yr of age; 18.9 to 23.1 kg BW) were fed the diet plus an expanded pork skin chew (~45 g) each day for 22 d. In vitro gastric digestibility of expanded pork skin chews increased with time, with chews being 54.7%, 58.6%, 76.4%, and 86.4% digestible after 6, 12, 18, and 24 h of gastric digestion, respectively. By contrast, gastric digestibility of rawhide chews was 7.6% at 6 h, slowly increased over time, and reached a maximum of 41.6% at 18 h. In vitro gastric plus small intestinal digestibility results indicated near complete digestibility of expanded pork skin chews at all times, whereas rawhide chews were 50 to 85% digestible. In vivo ATTD of DM, OM, and N were greater (P < 0.05) when dogs were fed expanded pork skin chews along with the basal diet, compared with the basal diet alone. However, chew intake did not change transit time measured with a wireless motility device. By contrast, motility index and contraction pattern of the colon were altered (P < 0.05) during chew feeding relative to control. Blood urea N concentrations were greater (P < 0.05) in dogs fed expanded pork skin chews, compared with baseline; this was not surprising, given the increased N intake and absorption from the chews. Intake of expanded pork skin chews resulted in reduced blood cholesterol concentrations (P < 0.05) and tended to decrease blood triglyceride concentrations (P < 0.10). Expanded pork skin had a greater DM digestibility than rawhide chews. In addition, expanded pork skin decreased blood cholesterol and triglyceride concentrations, which may justify further research in this area.
咀嚼物是宠物产品行业的重要组成部分，其中许多产品具有减少牙菌斑或牙垢形成的潜力。然而，它们的消化特点和肠道通过时间实际上是未知的。进行了两项实验，以确定健康成年犬在喂食体重控制商业饮食和膨化猪皮咀嚼物时，膨化猪皮咀嚼物和生皮咀嚼物的体外 DM 消化率、表观全肠道消化率（ATTD）、胃肠道通过时间和血液代谢物测量。在实验 1 中，使用模拟胃和小肠消化的体外方法来确定膨化猪皮咀嚼物和生皮咀嚼物的 DM 消化率。在实验 2 中，在 22 天基线阶段后，10 只专门饲养的、完整的雌性狗（5 至 5.5 岁；18.9 至 23.1 kg BW）每天喂食饮食加膨化猪皮咀嚼物（约 45 g），持续 22 天。膨化猪皮咀嚼物的体外胃消化率随时间增加，分别在 6、12、18 和 24 h 的胃消化后，咀嚼物的消化率为 54.7%、58.6%、76.4%和 86.4%。相比之下，生皮咀嚼物的胃消化率在 6 h 时为 7.6%，随时间缓慢增加，在 18 h 时达到最大 41.6%。体外胃加小肠消化率结果表明，膨化猪皮咀嚼物在任何时候都接近完全消化，而生皮咀嚼物的消化率为 50%至 85%。与单独喂食基础饮食相比，当狗同时喂食膨化猪皮咀嚼物和基础饮食时，DM、OM 和 N 的体内 ATTD 更高（P < 0.05）。然而，咀嚼物的摄入量并没有改变无线动力设备测量的通过时间。相比之下，与对照相比，在喂食咀嚼物时，结肠的动力指数和收缩模式发生了变化（P < 0.05）。与基线相比，喂食膨化猪皮咀嚼物的狗的血液尿素氮浓度更高（P < 0.05）；考虑到咀嚼物中增加的氮摄入和吸收，这并不奇怪。膨化猪皮咀嚼物的摄入量降低了血液胆固醇浓度（P < 0.05），并倾向于降低血液甘油三酯浓度（P < 0.10）。膨化猪皮的 DM 消化率高于生皮咀嚼物。此外，膨化猪皮降低了血液胆固醇和甘油三酯浓度，这可能证明在这方面进行进一步研究是合理的。
