Medicated *chick* starter has amprolium in it, but *most* do not have antibiotics in them.
Quote: Quote: How Amprolium works
Structurally, amprolium mimics thiamin (Vitamin B1) which is required by coccidia for normal growth and reproduction. When coccidia ingest amprolium, they experience thiamin deficiency and starve from malnutrition. amprolium has been experimentally administered at many times the recommended dosage and duration with no signs of toxicity.
When Amprolium works
Amprolium stops coccidia at a critical stage in the host animal's small intestine to prevent more damaging coccidiosis in the large intestine. By acting on the young asexual stages of the coccidia life cycle, amprolium allows exposure to first-generation schizonts, so the host animal can develop natural immunity to coccidia. This makes amprolium effective as a preventive therapy.
-Kathy