How long on Medicated Feed for chicks?

[BK79]

My chicks are exactly 3 weeks old now and have been on medicated feed. Thinking of stopping after 4 weeks and going to non medicated purina gamebird feed 30%....
is this ok? or do they need the medicated feed longer?

 

[gryeyes]

Medicated feed should be provided for at least two weeks after chicks have been "on the ground" out of their brooder. The amprolium helps chicks resist the cocci and build chicks ou up an immunity to it.

You don't build up an immunity to something unless you're in contact with it. Same for chicks.

If you stop feeding them medicated feed too early, and they encounter cocci, they won't have any defense against it. No built-up immunity.

I forgot that once... Didn't have a grow-out coop set up when 33 chicks were ready to go out of the brooder. Stopped the medicated feed at eight weeks, like usual (usually I put them out around five or six weeks old, then let them integrate with the rest of the flock) but they spent another two weeks in the brooder before going out to their grow-out coop. I just thought, okay, 8 weeks, it's time.)

As a result I lost ten 10-week old chicks in three days, and two adult chickens within a week, due to the load of cocci infecting the chicks and being spread when the youngsters joined the main flock. Had I not treated everybody with Corrid once I realized what was going on, I'm sure I would have lost more birds.