If no fleas, why the Advantage and why weekly? He is using it topically between the shoulder blades? I think I would stop the Advntage.
Did you ever have flea collars on them? Do you have collars on them? Odd it is all 3 and only the neck area.
It's advantage multi, he was thinking maybe it was walking dandruff but I went back to the vets again yesterday and we did a skin scraping and it's not mites or walking dandruff. Advantage multi kill many mites so were playing safe. We now have moved on thinking its a fungal infection, it's only making one pup really lose hair the other two have the itch but aren't losing near as much hair. We did take a piece of hair and will see in 5-10 days if there's a growth, we decided to treat for a fungal anyhow in the meantime, they are on amoxicillin incase of an infection and I'm using Selsun sandruff /tinea versus colour shampoo on them every second day for a 7-10 days. I guess we will see how this turns out.. Praying I see results in a few days.
Glad you went back to the Vet and some tests are being done. Having done some breeding of dogs myself in the past, this just strikes me as really odd it is all 3 and only the neck area. I take it you have noticed no other hair loss anywhere else on the body? Did the Vet tell you to use that shampoo? Us that the human shampoo?
I am not that familiar with your breed but, as a breeder, and assuming I know the lineage of my dogs and who I got them from, I would be contacting the owners of the sires and dams to see if they would be forthcoming with any similar problems in their lines.
You can also look up the Miniature Poodle National Breed club as they often list potential genetic problems for the breed. Try doing a Google search for diseases or genetic diseases for your breed.
Good luck and do keep us posted.
I have contacted them and they never had that problem. Yes it's ok to use that human shampoo I also read it online. Ill give it a week & see what happens.
You might try the oatmeal hampoo then do a diluted vinega rinse,