Transfer of blood urea nitrogen to cecal microbes and nitrogen retention in mature rabbits are increased by dietary fructooligosaccharides

Xiao Min, Jin Xiao, Kiyonori Kawasaki, Xiao Li, Ei Sakaguchi

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5 Scopus citations


To estimate the effect of fructooligosaccharides (FOS) on N utilization, seven mature rabbits were fed a diet containing 5% glucose or FOS for 8 days. During the last 5 days, total feces and urine were collected to measure N levels (Experiment 1). To examine N transfer from the blood to cecal microbes, eight rabbits were fed the same diets as in Experiment 1. After 9 days of feeding, 2g of glucose or FOS was given orally. Two hours later 20mg of 15N-urea was administered via the ear vein, and 1h later cecal and blood samples were collected (Experiment 2). Urinary N excretion was lowered by FOS feeding (P<0.05). Total bacterial N and 15N in the cecum was significantly higher in FOS-fed animals (P<0.05). Urea N in the cecum was lower in FOS-fed rabbits (P<0.05). Similarly, 15N atom % excess of cecal urea N was also lower in FOS-fed rabbits than in glucose-fed rabbits. These results suggest that FOS in the diet increases the transfer of blood urea N to the cecum for bacterial synthesis, thereby increasing N utilization.

Original languageEnglish (US)
Pages (from-to)671-677
Number of pages7
JournalAnimal Science Journal
Issue number6
Publication statusPublished - Jun 2014
Externally publishedYes



  • Bacterial N
  • Blood urea
  • Fructooligosaccharides
  • Mature rabbit
  • N retention

ASJC Scopus subject areas

  • Agricultural and Biological Sciences(all)

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