Botanicals have been proposed as a substitute for antimicrobials in swine diets because of their natural antibacterial activity. Echinacea, a botanical grown in Iowa, was compared with an antibacterial nursery feeding program consisting of 50 g of Mecadox per ton. At the tested Echinacea levels (0, 0.10, 0.25, and 0.50%) in experiment I, Mecadox generally elicited a positive response for daily gain and feed efficiency over the Echinacea treatments during the nursery phase. In experiment II (Echinacea levels of 0, 1.5, and 3.0%), there were only minor or no differences between Mecadox and the various Echinacea additions, indicating a high level of pig health. The cumulative data were inconsistent, with the 3.0% Echinacea often showing improved feed efficiency and daily gain (weeks 0–3) and better daily gain (weeks 0–3 and 0–5) compared with 0.0 or 1.5% Echinacea. Periodic data (Table 5) numerically suggested that the 3% Echinacea supplement enhanced daily gain equal to the Mecadox diet.