“How do hens encourage their football teams?”/“They egg them on.”

A hen riddle is:
 
Q: How do hens encourage their football teams?
A: They egg them on.
 
The joke has been cited in print since at least 2001.
 
         
20 May 2001, Sunday Telegraph (Surry Hills, New South Wales), “The Funday Telegraph” by Matthew Frilingos, pg. F1:
Q How do hens encourage their football teams?
They egg them on.
 
CPFC BBS   
furry mascots and football jokes.     
Teaser
07-06-2001, 08:59 PM
(...)
How do hens encourage their football teams ?
They egg them on !
           
Google Books
Sports Jokes
By Hugh Moore
Edina, MN: ABDO Publishing Company
2004
Pg. 13:
How do hens encourage their football teams?
They egg them on!
   
Google Books
1001 Cool School Yard Jokes
By Glen Singleton, Nicolas Brasch and Barbara Whiter
Heatherton, Victoria: Hinkler Books
2004
Pg. 92:
How do hens encourage their football teams?
They egg them on!
 
Google Groups: Humor Club
Humor & Sports
R.K.
11/12/05
-: HUMOR AND SPORTS ! ! :-
>>1. What tea do footballers drink ?  Answer: Penal-tea.
>> 2.Why didn’t the dog want to play football ?  —Answer: It was a boxer ! !
>>3.  How do hens encourage their football teams ?—-Answer:- They egg them on ! !
     
Google Books
Penguin Pocket Jokes
By David Pickering
London, UK: Penguin Books
2006
Pg. ?:
How do chickens encourage their young?
They egg them on.
 
1 April 2007, Sunday Territorian (Darwin, Australia), “Jokes,” pg. 32:
How do hens encourage their football teams? They egg them on.
 
Twitter
John Barnes
@jbitwc2009
How do hens encourage their football teams?They egg them on!
8:39 AM - 10 Dec 2009
   
Google Books
Gigglers: Sporty Jokes
By Toby Reynolds
London, UK: Scholastic UK
2016
Pg. 18:
Q. How do hens encourage their favourite badminton players?
A. They egg them on.
 
Twitter
Lucky Score
@LuckyScoreNet
How do hens encourage their football teams
?
They egg them on !
#Joke from #SportJokes in #Jokes, #Humor and #Satire
8:34 PM - 9 Apr 2018