Table 1.

Concentrations of effective components in the experimental diets¹, g/kg.

Items	Control	Star anise	Essential oil	Leavings
Trans-anethole	BD	0.204	0.204	BD
Estragole	BD	0.003	0.003	BD
Anisaldehyde	BD	0.002	0.002	BD

Abbreviation: BD, below detection.

¹Control, basal diet; Star anise, Control +5 g/kg star anise; Essential oil, Control +0.22 g/kg essential oil; Leavings, Control +5 g/kg leavings.