Little piggies sent to the abattoirs in the end (4)
I believe the answer is:
toes
'little piggies' is the definition.
('this little piggy' nursery rhyme)
'sent to the abattoirs in the end' is the wordplay.
'in the end' indicates one should take the final letters.
The last letters of 'sent to the abattoirs' are 'TOES'.
(Other definitions for toes that I've seen before include "Foot digits" , "What Pobble lacked (Lear)" , "Divisions of foot front" , "Lower digits" .)