Human-flora-associated (HFA) mice produced by oral inoculation with human fecal suspension to germfree mice were examined on the changes of the composition of fecal flora when they were given high-meat (HM) and high-bran (HB) diet and fructooligosaccharides (FOS). The composition of fecal flora of HFA mice was similar to that of the inoculated human feces. Number of enterobacteriaceae significantly increased with HM diet and decreased with HB diet to the level with basal diet. Bacteroidaceae, clostridia and streptococci decreased their numbers with HB diet, while the number of bifidobacteria in HFA mice fed HB diet was significantly higher than those fed HM or basal diet. The rate of bifidobacteria to total bacteria increased and the numbers of bacteroidaceae and enterobacteriaceae tended to decrease in HFA mice administered FOS solution, but the differences were not statistically significant. These results indicate that the changes of floral composition by different dietary components can be observed more obviously in HFA mice than in humans.

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Five non-selective media (medium 10, medium 10 supplemented with 1% extract of eucalyptus leaves, medium 10 with 1% fecal extract of koala, M98-5 and EG agar) by the plate-in-bottle method and two non-selective media (EG agar plate and BL agar plate) by an anaerobic jar method were evaluated for isolation of fecal bacteria in koalas. The predominant isolates were bacteroidaceae, clostridia and eubacteria as obligate anaerobes and enterobacteriaceae as facultative anaerobes. EG agar by the plate-in-bottle method was a suitable medium for isolation of obligate fecal anaerobes from the animals. All the isolates could not be identified to species presently recognized by using currently accepted identification protocols.

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The viability of freeze-dried cells of bifidobacteria (B. thermophilum ATCC 25525) in broiler starter rations was monitored at different storage temperatures during a twelve-week period. A total of five treatments (control plus four bifidogenic factors), at low (1.55% moisture, a_w<0.4) and high water activity (10.52% moisture, a_w = 0.64) were included in the study. Results indicated that lower moisture and water activity enhances the survival of bifidobacteria when incorporated into feeds. Refrigeration temperatures (5°C and - 18°C) also increase the survival of bifidobacteria in rations stored for up to twelve weeks. Bifidogenic factors, when included in the feeds, had a limited protective effect on bacterial survival. The use of probiotics, containing bifidobacteria, is an area that needs to be closely evaluated before they can be added to animal rations under commercial conditions.

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This paper describes a recommended method for the detection and enumeration of lecithinase-positive clostridia in fecal specimens. The use of specimens treated at 80°C for 10 min in parallel with unheated specimens with both selective and nonselective media is needed for the enumeration of lecithinase-positive clostridia in fecal specimens, when the numbers are less than 10⁴/g.

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