Which breed designations should I be careful of when searching to adopt a puppy

As my puppy search continues, I've been perusing various humane society and rescue group websites. There are certain breeds (pits, rotts) that I'm not interested in at all, and I'm worried about how these groups label their pets in order to move them easier.

So my basic question(s) is this: what are the rules for such labels? Do these groups try to err on the side of adoptability when calculating and advertising breeds? And if so, what are the typical substitutions just so I can be aware?

Here's an example: http://www.bvhumane.org/listman/listings...

Not just interested in this wee one (more the general practice), but she's advertised as a lab/chow mix.

What do you think?

Thanks, in advance, for your consideration.

You are so wise to be searching selectively for the right breed!

My bet is that this puppy has some black on her tongue. That often gets the "chow" label. However, many retrievers have black spots on their tongues, so that's not a sure thing. This pup could be either a lab mix or a pit mix ... it's adorable whatever it is.

Yes, most rescues really promote their breeds. However, as someone who works with aggressive dogs, I must say that pit bulls and Rottweilers can be very sweet and affectionate dogs who are not at all aggressive, while cocker spaniels and golden retrievers can sometimes be aggressive. There is no breed that is 100% non-aggressive. I have a Greyhound and while Greyhounds are among the gentlest dogs around, once in a while there is an aggressive Greyhound. EVERY breed has aggressive individuals in it. There is no breed that is immuned to behavioral problems.