First appearance of this word seems to be in the 2002 book "Sally Dog Little" with a character called Swiggity Jim.
This is now a 2013 meme (knowyourmeme) , and looking up swiggity on twitter brings up a lot of humour.
A 2013 book "100 Days in Deadland" uses this in a poetic form. from google search : “Swiggity swire, guess what's on fire,” I murmured and pulled the trigger. Then smiled. “Swiggity swed, guess what's dead.