Any idea of what they are

[kendracandraw]

While they look bitten/cut off, there is a lady in Texas that has been working with curly tailed rats, she calls them "doodle rats".

http://tinyfeetrodentry.webs.com/Snicker_Doodle2.jpg

So if they were for sure not born with tails, and have the bobbed look it could be a new type...