Dobbin's diet (4)
I believe the answer is:
oats
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">dobbin's diet</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for oats that I've seen before include "Cereal for porridge" , "Sow wild ones in disreputable youth" , "Edible grass seeds" , "Porridge mix" , "Grains or porridge" .)