Animal trade's underhand dealings (6,8)

I believe the answer is:

monkey business

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'underhand dealings' is the definition.
The definition suggests a singular noun which matches the answer.

'animal trade's' is the wordplay.
'animal' becomes 'monkey' (monkey is a kind of animal**).
'trade' becomes 'business' (I've seen this before).
'monkey'+'business'='MONKEY BUSINESS'

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(Other definitions for monkey business that I've seen before include "Mischievous behaviour" , "Marx Brothers film" , "fiddle" , "mischief" , "may be amusingly projected" .)

I've seen this clue in The Independent.

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