There is an assortment of folk plays with the theme of "The old horse" or "hoss" and some of the verses of
song & spoken dialogue are very similar to the oft heard words to this shanty.
See here
and here

Although these particular sites make no claim to ancient authenticity, they do use words & phrases handed down through generations.
There is also, of course, the ceremony of broaching the first cask of "salt beef" which uses the same theme,
the crew being suspicious as to the origin of said "beef", liking it to horse meat.
By the stars, I'd give me eye teeth to 'ave bin an ancient mariner (not)!