2 yrs cocker spaniel scratching and chewing

Question
I have had cocker spaniels since 1984 and oldest was 17 1/2 laid her to rest in 2001 female our male was a UKC champ. and was laid to rest in 1994 he was 8 1/2 yrs are last cocker spaniel was 14 yrs male laid last year Oct 26,2010 we miss all of them and they were heathy dogs.My question is this i just got another cocker in aug 6,2010 and she had been somewhat abuse from what we can tell she is a very lovely dog but we have several issue with her. We changed her food to a high protein because of her poop,she always scratching and chewing her skin our vet can not fine anything wrong with her but when we first got her she had second skin infection so she was on medication to help that she still scratches like she going to town or something it drives us nuts. The other this is this dog is not a morning dog she does not like to go out early or at 10 am either. She also does not like to eat till night time unless we hold the bowl for her to eat. Plus she is able to get under our bed and sleep there we do have a cage for her she does go in once in a while we need some help on this i am not sure what to do about this type of behavior she is totally different from are other three cocker spaniels.

Answer
What exactly did your vet do?  I'm assuming he ran a blood panel?
And what med was she on (dosage & length of treatment?) and how was the skin infection diagnosed?
Did your vet take skin cells (either with a piece of tape or a light scrape) and tell you it was bacterial or yeast?  What topical advice did he give?

What are you feeding her?

It doesn't sound like you have any real behavioral problems.

If she's not on any meds currently I'd certainly try antihistimine therapy.  Did your vet suggest that?  You have a 30% chance that would solve the problem.  I can give you info and dosage if you'll write me directly at DeeBeck7765@aol.com.
Delores