Dog breeder with retainer at sixes and sevens (8,7)

I believe the answer is:

aberdeen terrier

'dog' is the definition.
(I've seen this before)

'breeder with retainer at sixes and sevens' is the wordplay.
'with' is a charade indicator (letters next to each other).
'at sixes and sevens' is an anagram indicator.
'breeder'+'retainer'='breederretainer'
'breederretainer' with letters rearranged gives 'ABERDEEN TERRIER'.

(Another definition for aberdeen terrier that I've seen is " Dog".)

I've seen this clue in The Telegraph.

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