Dog caught little Oliver (6)

I believe the answer is:

collie

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'dog' is the definition.
(collie is a kind of dog)

I don't understand how the rest of the clue works.

(Other definitions for collie that I've seen before include "shepherd's gofer" , "See 2" , "Popular sheepdog like Lassie" , "Type of sheepdog" , "Sheep-herding dog" .)

I've seen this clue in The Sun.

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