Plow pullers (4)
I believe the answer is:
oxen
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">plow pullers</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for oxen that I've seen before include "Horned farm animals" , "Bulls, buffaloes, etc" , "Domestic bovines" , "Lowers" , "Domesticated bovine draft animals" .)