Feed bag contents (4)
I believe the answer is:
oats
'feed bag contents' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for oats that I've seen before include "Grains or porridge" , "Sow wild ones in disreputable youth" , "A cereal crop" , "Porridge mix" , "Porridge ingredient" .)