Cranberries (Vacciniummacrocarpon aiton) in dog nutrition: influence on diet digestibility and palatability and in the course of urinary tract infections

ABSTRACT The objective was to evaluate the effects of cranberry on blood and urinary parameters of dogs (experiment I), digestibility of nutrients (experiment II), palatability of diet (experiment III) and the influence of cranberry on E. coli UPEC-MRHA fimbriae in vitro (experiment IV). For experiment I and II, ten dogs were fed with diets containing 0% or 0.4% cranberry for 30 days. Experiment III compared the diets containing 0% and 0.4% cranberry using 16 adult dogs. There were no statistical differences (P>0.05) in the blood parameters evaluated. Dogs consuming cranberry presented lighter color and appearance of urine, compared to the control group (P<0.05). The diet containing cranberry showed higher digestibility of dry matter, organic matter, ether extract, higher metabolizable energy (P<0.05) and reduced fecal sialic acid concentration (P<0.05) compared to the control diet. There was no influence of cranberry on the formation of fimbriae of E. coli UPEC-MRHA. There was a lower intake ratio of the diet containing cranberry (P<0.05). The inclusion of 0.4% cranberry increases the digestibility of nutrients and influences the color and appearance of urine of dogs. However, it reduces diet palatability and does not alter the adhesion of E. coli UPEC-MRHA in vitro.摘要 本研究旨在评估蔓越莓对犬血液与尿液指标的影响（实验I）、养分消化率（实验II）、日粮适口性（实验III），以及蔓越莓对大肠杆菌UPEC-MRHA菌毛（E. coli UPEC-MRHA fimbriae）的体外（in vitro）影响（实验IV）。实验I与II中，选取10只犬饲喂添加0%或0.4%蔓越莓的日粮，连续干预30天。实验III采用16只成年犬，对比添加0%与0.4%蔓越莓的日粮饲喂效果。检测结果显示，各组血液指标无统计学差异（P>0.05）。饲喂蔓越莓的试验组犬尿液色泽与外观较对照组更浅，差异具有统计学意义（P<0.05）。相较于对照组日粮，添加蔓越莓的日粮其干物质、有机物、乙醚提取物的消化率更高，代谢能水平更高，且粪便唾液酸浓度更低，上述差异均具有统计学意义（P<0.05）。蔓越莓对大肠杆菌UPEC-MRHA菌毛的形成无显著影响。含蔓越莓的日粮采食量更低，差异具有统计学意义（P<0.05）。综上，日粮中添加0.4%蔓越莓可提升犬的养分消化率，改变犬尿液的色泽与外观，但会降低日粮适口性，且不会在体外改变大肠杆菌UPEC-MRHA菌毛的黏附特性。