I miss your Buckeye trivia, but some tennis trivia, cat gut strings are actually made from sheep intestines!
From wiki ;
Catgut is a type of cord[1] that is prepared from the natural fiber in the walls of animal intestines.[2] Usually sheep or goat intestines are used, but it is occasionally made from the intestines of a hog, horse, mule, pig or donkey. While the name contains the morpheme "cat", strings have never been made from the guts of cats.
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