I feel it is a personal choice, but maybe a little knowledge will help you make that choice. Of course, check the label to confirm what the medicine in that specific feed is. I’ll assume it is Amprolium, it almost always is, but if it is something different then what I’m about to say is obviously just nonsense as far as you are concerned.
Amprolium is not an antibiotic. It is a thiamine blocker that reduced the reproduction rate of the bug that causes Coccidiosis. In the dosage in medicated feed it does not stop all reproduction but it certainly limits it. If the chick is exposed to that bug for two to three weeks it will develop an immunity to it as long as the numbers don’t get out of hand. If the numbers get out of hand the chick can get really sick or die. The dosage in medicated feed is set to allow it to develop immunity but not get sick.
The life cycle of that bug includes some time in wet conditions. A wet brooder or dirty drinking water is a breeding ground for that bug. If you can keep your brooder relatively dry and keep the drinking water fresh, that is usually enough to control the bug. But some strains of that bug are stronger than others, you still need to watch for symptoms of Coccidiosis. A wet coop, run, or brooder are all danger spots. Wet is the problem.
Once Coccidiosis is in your flock it is always in your flock. Even if your birds have developed immunity they are still carriers.
Before the Amprolium can limit the reproduction of that bug and the chicks can develop immunity, the bug has to be present. If you keep your chicks in a sterile brooder and that bug is never introduced they cannot develop that immunity. A fairly common occurrence on this forum is that people feed medicated feed in a sterile brooder and stop feeding medicated feed when they hit the ground and are first exposed to the bug. Then the chicks get sick and people complain about the medicated feed not working.
I do not use medicated fed either. I know I have Coccidiosis in my flock because I had some chicks come down with it once. These were being raised by a broody hen, by the way, and the weather was really wet just after they hatched. The run was a muddy mess. So I introduce dirt from my run where the adults poop into the brooder about Day 2 and add more every three or four days to keep up a steady yet limited supply of that bug. It also gets any probiotics the adults have into the chicks and gives them grit. To me a win-win-win. I keep the brooder really dry and the water fresh. Mine don’t have any problems when they hit the ground, they already have the immunity they need.
If you have a history of a strong strain of Coccidiosis them medicated feed might be a good idea. Maybe with this information you can use it wisely if you decide to use it.
