Need help identifying what's wrong with this chick

[Chick2Much]

Hey everybody I have an odd looking runt chick that's never caught up to it's hatch mates. I thought she was just going to be an odd naked neck looking cochin that's not feathering out properly but that's until I noticed her skin starting to show lumps and bumps. She eats and drinks fine is active but whatever she has doesn't look good or comfortable and if it's infectious I need to know so there's no cross contamination between these chicks and my main flock. They're still indoors under a brooder lamp since it's been far too rainy to go outside yet. Other chicks in the group, silkies and another cochin are doing well and look good. You can see the size and develop difference between her and the other chicks.

 

[Eggcessive]

Do the others peck on her or trample her? It looks like her chest is bruised. Is she lying in wet spots? I would give a 5 day course of Corid to treat for possible coccidiosis if she doesn’t perk up with some vitamins first. Something like Poultry Cell or NutriDrench 1 ml per day might be good to try first. Discontinue vitamin during Corid, and that can be used afterward. Corid dosage is 2 tsp of liquid Corid per gallon of water for 5-7 days. Treat them all, and watch that she is not picked on.

 

[getaclue]

She doesn't look to be the same type as the others, and it looks like they're pecking at her.

 

[Chick2Much]

No pecking from the other chicks. She scratches at herself but no signs of mites or lice. The bruising is hard lumps that you can feel under the skin that are on her breast and legs. She's a buff cochin from Ideal same shipment as the other cochin in the pics. I've ordered many chicks from them through the years and never one this far off breed standard. The feathers that do come in are frizzled looking but she's never had any on her neck. I'm already adding vitamins to their water but will treat with corid too.