The Kingsmen's version was recorded in one take for a total cost of $50 in Portland, Oregon. To my ear, a stray background voice interjects what sounds like the word "fuck" at around 58 sec. According to Wiki, it was the drummer who had dropped a stick. Listen for yourself:
The Kingsmen's Louie Louie made a clean break with the pop music of the 1950's and early 60's. They antedated "The Beatles" by several months (at least in America) and The Kinks (who they more closely resemble), by a year. Things were never the same afterwards. I blame youthful hormones.
[added] Slurred and ambiguous lyrics had a long history with censors. For example. Shake, Rattle And Roll.