Penetration of Intestinal Wall of Rabbit by Yeasts

Abstract

Casagrandi 1 early concluded that blastomycetes seldom penetrate the mucous layers of the intestinal wall. Positive results were explained on the basis of existing injuries which escaped detection. Fisher, 2 however, recently found that yeast fed fasting dogs is absorbed like bacteria into the portal circulation. Cells injected into the portal vein also proved that yeasts can invade all the organs, the distribution varying with the amount injected.

In this study the blood of 30 rabbits, daily fed large doses of viable yeast cells, was frequently cultured. The heart's blood, bile, the spinal cord, and portions of certain of the vital organs including the liver, lungs, spleen and kidneys were cultured upon autopsy. Blood sera of the animals were also periodically examined for the presence of agglutinins.

Before feeding the blood of experimental and control animals was cultured and found to be free from yeasts. The yeasts isolated from the blood and organ cultures were compared with the strain which each animal received.

The following varieties of yeast were used: Saccharomyces carls-bergensis, Saccharomyces cerevisiae, Saccharomyces glutinis, Sac-cltaromyces turbidans, Endomyces albicans, Monilia tropicalis, Torula cremoris, Hunter's yeast isolated from oysters, a commercial pressed yeast, Saccharomyces ellipsoidens, Willia saturnus, Zygo-saccharomyces mandshuicus, Monilia albicans, Monilia Candida, Mycoderma cerevisiae, Oidium albicans, Torula hansen, Torulopsis sanguinia, and yeast isolated from a sore throat. The first 9 species listed were recovered from the blood after feeding. All, with the exception of a commercial pressed yeast were taken from stock cultures in the laboratory. Suspensions of the commercial yeast were prepared by dissolving a 15 gm. cake in 50 cc. saline, 4 to 6 cc. of which were given certain of the rabbits daily. The remaining animals were fed saline suspensions of yeasts grown on dextrose agar slants at room temperature.