Children's Book Authors/Illustrators discussion

I am working on a manuscript that I would like to submit to a publisher. I am struggling with putting the prosal together. Is it a good idea to talk about prior self-published work or not? Will it help/hurt or not have any impact at all. I was going to include it in the "Biography" section.
My prior work is in the same genre (Childrens book), but still low on sales rank on Amazon (that's another possible question!). This is my prior self-published book fyi
http://amzn.com/B01CJ2D2JC

I wouldn't use the term self-published. It's certainly nothing to be ashamed of but has a lot of negative stigma attached. Let your work speak for itself.