Impacts of atmosphere of incubation, mucin supplementation, and immune status on the in vivo growth of E. faecalis ATCC 29212. In all panels, solid lines represent significant and valid regressions using Gompertz's equation, and dotted lines indicate that the regression did not fit or failed the presumptions of normality or homoscedasticity (see Table S1 in the supplemental material). (a) Growth in neutropenic mice infected with inocula prepared under conditions of anaerobiosis (dotted gray line) or anaerobiosis plus mucin (solid black line). (b) Growth in neutropenic mice infected with inocula prepared under conditions of aerobiosis (dotted gray line) or aerobiosis plus mucin (black dotted line). (c) In vivo growth curves for immunocompetent animals infected with inocula prepared under conditions of anaerobiosis plus mucin (solid black line) or anaerobiosis (gray interrupted line). In panel c, data points at 26 h (black) and 14 and 26 h (gray) overlap.