A comparison of the gastrointestinal tract in germ-free and conventional mice fed an amino acid mixture or purified whole-egg protein.
An amino acid mixture diet(AA) simulated with purified whole-egg protein and a purified whole-egg protein diet(WE) were given to ICR strain male germ-free(GF) and conventional(CV) mice for three weeks from five to eight weeks of age. All mice were killed at eight weeks of age and the gastrointestinal tracts were removed. The lengths of the small intestine were measured and six parts, i.e., the stomach; upper, middle and lower parts of the small intestine; cecum; and colon and rectum were separated, and each part (with contents) was weighed immediately. The contents were removed from each part by washing with distilled water. For the gut without contents, only total nitrogen(TN) was estimated and for the gut contents, TN, protein nitrogen(PN) and water-insoluble nitrogen(WIN) were estimated. The fresh weight of cecum with contents per 100 g of body weight of GF mice fed on AA diet, 2.07 +/- 0.11 g (mean +/- SE), was lighter than that of GF mice fed on WE diet, which was 4.51 +/- 0.28 g. The weight and length of the small intestine of AA diet groups were smaller than those of WE diet group. TN and PN(mg) in whole gut contents per 100 g of body weight in the WE diet group were higher than those in the AA diet group and high TN and PN were observed in GF mice. The PN per TN and WIN per PN of gut contents were affected more by the presence of the flora than by the difference in diets, and CV mice showed high values. The TN of the intestinal tract excluding contents showed no differences in GF and CV mice fed on either diet.
D000596:Amino Acids / Q000008:administration & dosage*; D000818:Animals; D004044:Dietary Proteins; D004064:Digestive System / Q000033:anatomy & histology / Q000187:drug effects* / Q000378:metabolism; D004527:Egg Proteins / Q000008:administration & dosage*; D005856:Germ-Free Life / Q000187:drug effects*; D051379:Mice; D009584:Nitrogen / Q000378:metabolism; D009929:Organ Size; D011506:Proteins / Q000378:metabolism; D012995:Solubility
D000596:Amino Acids; D004044:Dietary Proteins; D004527:Egg Proteins; D011506:Proteins; D009584:Nitrogen