Effects of probiotic feeding on fecal bacterial population.

a, bMean values within a column with different superscript letters were significantly different (P<0.05). The data are shown as the mean ± standard deviation.列内带有不同上标字母（如a、b）的均值间存在显著性差异（P<0.05）。 数据以均值±标准差的形式呈现。