A cow riddle is:
 
Q: What do cows like to listen to?
A: Moo-sic (music).
 
The joke was printed in newspapers in 1985 and 1988.
 
     
11 October 1986, Rockford Register Star, “Just For Laughs,” Pennywhistle Press, pg. 3, col. 4: 
Question: What kind of music do cows listen to?
Answer: Country Moo-sic.
Peter McElwain, 9
Blauvelt, N.Y.
 
23 June 1988, The State (Columbia, SC), “Joke of the Week,” The Mini Page, pg. 3, col. 2:
Q: What do cows like to listen to the most?
A: Moosic.
Bonita Johnson
301 Goodrich Street
Columbia, S.C. 29223
 
31 January 1995, Honolulu (HI) Star-Bulletin, “3-2-1- Contact,” pg. B-4, col. 1:
What do cows like to listen to down on the farm? The answer: Moo-sic!
   
Google Groups: alt.fan.art-bell
Mad cow jokes.
Gomer Pile
2/25/01
What does a cow listen to?
Moosic
 
Google Books
1001 Cool School Yard Jokes
By Glen Singleton; Nicolas Brasch; Barbara Whiter
Heatherton, Victoria (Australia): Hinkler Books
2004
Pg. 43:
What do cows listen to?
Moosic.
     
Google Books
Sensible Nonsense.. Frank’s Comic Pack:
Humour Pack Series
By Frank Paul
BookBaby
2014
Pg. ?:
What do cows like to listen to? Moosic!
   
Google Books
LOL: A Load of Laughs and Jokes for Kids
By Craig Yoe
New York, NY: Little Simon
2017
Pg. 265:
Q: What kind of music do cows like to listen to?
A: Moo-sic!
 
Twitter
Lucky Score‏
@LuckyScoreNet
What do cows like to listen to?
Moo-sic!
#Joke from #CowJokes in #Jokes, #Humor and #Satire
2:58 AM - 8 Oct 2017