Feathers NOT right

[Gammas Bearded Babies]

Yall I'm not sure what I'm dealing with and need your help!
Porcelain Belgian d'uccle 16 months old shown in video here along with video/pic of couple feathers from her neck.
She's not the only one wirh this...but her neck looks much worse whereas my black Silkie has only 2 strands of her tail left.
I removed all bedding from run and coop.
I have sprayed down the entire area with Permethrin 10 and all birds have been sprayed with Elector PSP as of a week ago.
Anyone recognize what I may be dealing with from this video/pic?
I have not seen any mites, lice or signs of worms. They all eat and drink normally and are laying like they usually do.
Thank you in advance for your assistance!

 

[sourland]

Some bird/birds in the flock is feather pecking/plucking them. Pick the bird in perfect feather, and that is most likely the culprit.

 

[BastyPutt]

Pick the bird in perfect feather, and that is most likely the culprit.

This is genius and I am embarrassed I never though of this as a troubleshooting method.

 

[sourland]

This is genius and I am embarrassed I never though of this as a troubleshooting method.

Can I have that in writing ? Not genius - just been around these creatures for a LONG time.

 

[BastyPutt]

Can I have that in writing ? Not genius - just been around these creatures for a LONG time.

Hahahaha! Credit where credit is due.

 

[Gammas Bearded Babies]

Some bird/birds in the flock is feather pecking/plucking them. Pick the bird in perfect feather, and that is most likely the culprit.

I don't think that is what is going on as this is the top girl in the flock. All 3 of my d'uccles have similar looking feathers around their neck area. My Silkie has no tail and is not molting.

 

[Gammas Bearded Babies]

Some bird/birds in the flock is feather pecking/plucking them. Pick the bird in perfect feather, and that is most likely the culprit.

I don't think that is what is going on as this is the top girl in the flock. All 3 of my d'uccles have similar looking feathers around their neck area. My Silkie has no tail and is not molting.

I can't get the videos to upload so here are better pics.

 

[sourland]

I don't think that is what is going on as this is the top girl in the flock.

It's not a dominance or bullying thing. Generally it starts during the winter when birds are limited in space. Grooming escalates to plucking, and it becomes a bad habit.

 

[Gammas Bearded Babies]

It's not a dominance or bullying thing. Generally it starts during the winter when birds are limited in space. Grooming escalates to plucking, and it becomes a bad habit.

Mine don't free range. They also have double the space now. So it wouldn't be getting worse - right?
Side note: I lost my favorite girl I was closest to a week ago and I don't wanna lose anymore! The vet said she had an auto immune disorder with her reproductive system which made her succumb to a fungal infection and mites. But the vet didn't think it looked like an infestation. She did advise I clean out all bedding in both run and coop and treat it all before new bedding which I did with Permethrin 10 and Elector PSP was used on each chicken on the vent, under wings and crest/neck area.