Comb turning grey

[Chooklover1]

We feed them rice, bird food and mealworms as they are pretty small birds I would say the hen is in 20-30-40 weeks old and we don't monitor the eggs we just come by and collect them as she sleeps with one other hen who is perfectly healthy

 

[Wyorp Rock]

We feed them rice, bird food and mealworms as they are pretty small birds I would say the hen is in 20-30-40 weeks old and we don't monitor the eggs we just come by and collect them as she sleeps with one other hen who is perfectly healthy

Can you clarify what the "bird food" is - is it like a poultry feed (Chick Starter, All Flock/Flock Raiser, Grower, Layer, etc.) or is this a bird seed mix?

I would cut out the rice and limit mealworms. Focus on the pullets eating a nutritionally balanced poultry feed.

Check your pullet over for lice/mites, see that she's drinking and eating o.k. Provide oyster shell free choice and see that her crop is emptying.

Photos of her and her poop may be helpful.