A question about fur

Hi all!  I haven't posted anything in months but Lucy (my newf) has a couple issues with her fur that I'm not sure what to do about.

The first one is that she has a dry brittle patch of fur on her lower back (near her tail).  The fur there is really thin and brittle and dry and doesn't feel nice at all.  The rest of her fur is really pretty and soft.  What is going on?  What can I do to fix it.  Is this the beginning of her "spay" coat?

The second thing is that I never took her fabric collar off her and she was getting wet a lot in an effort to keep her cool.  Well the collar got all gross and stinky (kind of mildewy smelling) so I took it off and now I can't get the smell out of her fur. I've bathed her twice and it smells ok for a couple days and then she starts stinking again. The only thing I know to do to get mildew out of anything is bleach and well, that's obviously not an option.  I've done a google search and it didn't yield anything useful.  Ideas??

oh, and I couldn't find any recent pictures of her on my work computer so I attached a baby picture!  Goodness, I can't believe she is a year this month! Time sure flies!

Thanks!!

I cut a big ole burr out of that area on her back about a month ago and then a couple weeks ago furminated all the undercoat thinking that the undercoat was the culprit but it hasn't gotten any better.  It isn't on the back of her legs where she'd pee on it or anything but on her back near the base of her tail.   Do you think the burr could have effected the hair?

I've been conditioning that area once a week and it helps for a couple days and then starts getting dry again.

Does conditioning help Rosie?

We haven't really been conditioning her backside area, apart from her regular monthly bath which we use oatmeal-based shampoo, but still no conditioner. You're right, the area is still a bit too high for her pee to dribble on, but perhaps it's because it's close to that general area where the acidity and germs tend to come from. Perhaps you could ask the vet/breeder if they've seen that in other Newfs.