Selenium is an essential trace element that can modulate the gut microbiome with an impact on host health. The present study aimed to evaluate the effects of organic (selenium-enriched yeast) vs inorganic (sodium selenite) selenium source on fecal end-fermentation products and gut microbiome of puppies from 20 to 52 weeks of age. Alpha and beta diversity of the gut bacterial community were affected by age but not by gender or selenium source. The relative abundance of taxa was differently affected by age, and the DNA concentration of all selected bacterial groups increased with age, although total volatile fatty acids (VFA), acetate, propionate, caproate and lactate concentrations decreased. Organic selenium was associated with a higher concentration of total VFA, propionate and butyrate, a higher number of DNA copies of Lactobacillus, and a trend to lower DNA copies of Escherichia coli. Effects on fecal microbiome during growth differed with selenium source. Females had higher fecal end-fermentation products related to protein degradation, whereas males had higher DNA concentration of Bifidobacterium. Organic selenium might be beneficial over inorganic for dog food supplementation due to the positive modulation of the gut microbiome observed in puppies.

中文翻译：

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肠道健康的补充硒源：对粪便微生物组和幼犬发酵产物的见解

硒是必需的微量元素，可以调节肠道微生物组，从而影响宿主健康。本研究旨在评估有机（富硒酵母）与无机（亚硒酸钠）硒源对20至52周龄幼犬粪便发酵产物和肠道微生物组的影响。肠道细菌群落的α和β多样性受年龄影响，但不受性别或硒来源影响。尽管总挥发性脂肪酸（VFA），乙酸盐，丙酸盐，己酸盐和乳酸盐的浓度降低，但分类组的相对丰度受年龄的影响不同，所有选定细菌组的DNA浓度均随年龄增加。有机硒与较高的总VFA，丙酸和丁酸浓度，较高的DNA拷贝数有关乳酸菌，并有降低大肠杆菌DNA拷贝的趋势。硒源对生长过程中粪便微生物组的影响有所不同。女性的粪便发酵产物与蛋白质降解有关，而男性的双歧杆菌DNA浓度较高。由于在幼犬中观察到肠道微生物组的积极调节，有机硒可能比无机硒对狗食的补充有益。