COLONIZATION OF CECAL MUCOSAL EPITHELIUM IN CHICKS TREATED WITH A CONTINUOUS-FLOW CULTURE OF 29 CHARACTERIZED BACTERIA - CONFIRMATION BY SCANNING ELECTRON-MICROSCOPY

Bacterial colonization of cecal mucosal epithelium in 3-day-old chicks administered a characterized continuous-flow (CF) culture of 29 micro organisms on the day of hatch was evaluated by scanning electron micro scopy. Extensive colonization of the mucosa was noted in the ceca of C F-treated chicks, with large colonies of bacteria located predominatel y within and between crypts. Cecal crypts from control chicks containe d only thin strands of mucus with a few bacteria. Individual cells and clumps of bacteria were observed bound to the mucosal epithelium in b oth CF-treated and control chicks. Colonization by CF culture bacteria was accompanied by an increase in the concentration of volatile fatty acids in the cecal contents and increased resistance to colonization by Salmonella typhimurium.