Pale, slow chicken - can't figure out why

[Rime]

Recently one of our largest, dominant hens became pale and lethargic, and would spend her time standing puffed up (but tail up), with her eyes closed. We've had unseasonably warm and wet weather until recently, so their run had become very damp. I figured worms might be the issue, so wormed the entire flock with fenbendazole. For the especially sick lady, I gave her a slightly higher dosage over three days instead of the single dose. I also took her into the garage to get closer attention and some warmth and nutri-drench.

After several days she improved markedly, and though still slightly pale, was much more active so I returned her to the flock. I figured it could just take her a bit to recover from any anemia she might have had, hence the paleness.

Now it's been several days however and she's not improved any further. Slightly pale, slightly less energetic than the others, but not near as bad as she was pre-worming. Could it just be lingering anemia?

What else should I try for her? Spinach? The others are looking great, and will get a final worming dose in a few days (10 days from initial).

 

[Eggcessive]

Nutri-drench contains iron, so spinach isn't necessary. Coccidiosis or enteritis may be a concern. Corid (amprollium) 2 tsp per gallon of water will treat coccidia, and if you can get a fecal float by a vet, it could rule out cocci, enteritis, and also persistent worms. Capillary worms can require 5 straight days of fenbendazole at 1/4 cc or ml per pound of weight.