Hello.
I walk my one year old lab in the countryside a lot so it's not unusual for her to get a bit muddy. The other day i noticed she had a patch of something under where her ear hangs down and assumed it was a bit of mud from a full on walk we'd had the day before that she'd cleaned up from everywhere else. I remember saying you need a bath my love but being really busy with cooking for family coming over and sorting the house so i thought no more of it 
last night i noticed it again properly and it had changed. I examined it and i don't know what it is - the fur is matted together and there is a bit of a mass of something, i sort of pinched the area to make it stand out and there appears to be some kind of sticky residue down in between the hair. It actually made me feel quite sick and i'm not generally a squeamish person.
what on earth is it? i have to take ds to school this morning and then i can phone and try and arrange to go in to see the vet with her. i think it also smells a bit - which i assumed was from the walk but am now worrying is this thing that smells. it's not mange or something is it?
really worried and feeling bad that i ignored it for a couple of days and put it down to dirt. really close to the dog and she's with me all the time - i feel bad i didn't realise it was something more and examine it properly but i was all caught up in being busy and it was under where her ear hangs down (labrador) so it wasn't noticeable. also she's just been in season so i was tending to focus more on her nether regions and behaviour than something on her skin.
any ideas would be great - i'm totally clueless as to what it is unless she had a little absess there and it burst or something?