Dog chewed up grannie’s slipper (8,7)
I believe the answer is:
springer spaniel
'dog' is the definition.
(springer spaniel is a kind of dog)
'chewed up grannie's slipper' is the wordplay.
'chewed up' indicates anagramming the letters.
'grannies'+'slipper'='granniesslipper'
'granniesslipper' with letters rearranged gives 'SPRINGER SPANIEL'.
(Other definitions for springer spaniel that I've seen before include "breed of dog" , "might this be barking?" , "one used to raise game" .)