Effects of right hemicolectomy on fecal nitrogen excretion in rats

The influence of right hemicolectomy (RH) on fecal nitrogen excretion was determined with selected protein levels up to 25%. The endogenous fecal N was determined by extrapolating protein intake to zero. Fecal N was higher in RH than in control rats at all protein levels used. However, the slope of regression curves describing fecal nitrogen excretion was greater for RH compared with the control group. The endogenous fecal nitrogen was not significantly different between the two groups of rats. The feces from rats fed with 25% of protein were partitioned into individual fractions by physical separation and a study was made of the distribution of nitrogen in the bacterial, soluble and fiber fractions of the stool. RH decreased the N excreted in the bacterial fraction by 33% (from 1.71 +/- 0.32 to 1.15 +/- 0.18 mmol/day) and increased the N excreted in the soluble fraction by 280% (from 1.60 +/- 0.30 to 6.08 +/- 1.16 mmol/day). These results show that the RH increased the fecal N excretion and that this N is mainly in the soluble fraction.