Table 5.
The optimal dietary LFP supplementation based on different indices for piglets.
| Items | Regression equation* | R 2 | P -value | Optimal dietary LFP levels (mg/kg diet) |
|---|---|---|---|---|
| AST activity in serum (U/L) | y = 0.0008x2-0.2528x + 54.469 | 0.770 | 0.006 | 158 |
| T-AOC activity in serum (U/mL) | y = −0.00002x2 + 0.0082x + 1.0195 | 0.860 | 0.001 | 205 |
| T-AOC activity in spleen (U/mL) | y = −0.00002x2 + 0.007x + 0.6721 | 0.862 | 0.000 | 175 |
| GSH-Px activity in spleen (U/mL) | y = −0.0024x2 + 0.733x + 532.31 | 0.713 | 0.046 | 153 |
| IgG of content in serum (μg/mL) | y = −0.0031x2 + 1.0567x + 415.58 | 0.928 | 0.009 | 170 |
*y is the dependent variable and x are the dietary LFP supplemental levels (mg/kg); LFP, licorice flavonoids powder.
SEM, total standard error of the mean (n = 6). Mean values within a row with different superscript letters were significantly different among diets with 0, 50, 150, and 250 mg/kg of LFP (one-way ANOVA, P < 0.05, Tukey's post-hoc test).