The Health of any Animal begins with the Intestinal Tract ...this is a combination of antibiotics designed to keep the intestinal walls healthy..when the Intestinal walls are healthy the bird is able to absorb all the nutrients from the feed you are giving him...this also aids in absorbing medicines, wormers or any thinng else you give orally...this prodcuts works like "MAGIC" on the Greens, Mud Fever, birds holding feed or 'locked-up' ..it will also help birds gain weight. 
The key to Healthy Fowl begins in the Intestines