Establishment of Microorganisms Isolated from Chickens in the Digestive Tract of Germ-Free Chickens

Abstract

Germ-free chickens were monocontaminated or dicontaminatcd with microoganisms isolated from the cecal contents and feces of chickens. In the case of monocontamination, the viablc number of oganisms in the alimentary tract considerably varied depending on the species or genus. Staphylococcus epidermidis, slreptococcus faecalis var. liquefaciens and Escherichia coli became established in much larger numbers in germ-free chickens than in ordinary birds. While Bifidobacterium thermophilum and Catenabacterium sp. were unable to become established, other anaerobic organisms and a strain of yeast became established almost at the same level as in the ordinary microflora. Anaerobic non-sporeforming gram-positive rods (AR), which were occasionally found in the ordinary chickens. were always well established throughout the gut of monocontaminated birds. In the case of dicontamination, the numbers of S. epidermidis, Catena-bacterium sp. and B. thermophilum were comparable to those in the ordinary microflora. Growth of S. epidermidis was suppressed by E. coli. Calenabacterium sp. and B. thremophilum became well established when giycn in combination with other bacteria, except that the establishment of B. theimophilum in combination with catenabaclerium sp. was irregular. Growth of AR was prevented when administered together with. E coli On the other hand, the numbers of E. coli and S. faecalis var. liquefaciens were continuously large even in the presence of any other bacterium.