I assume you're being sarcastic?
Please. Sure, there are some passing incidental references to slavery in Mississippi's Declaration of Secession (the subject could hardly be ignored because it was in all the papers at that time), but if you can try to read between the lines (the way it was intended to be read), you can see that it really just takes up where the Declaration of Independence left off.
Here, try to read it again, with fresh eyes.
http://americancivilwar.com/documents/causes_mississippi.html
And try for once to appreciate the subtleties and nuances that were carefully designed for posterity.