Treated like chickens, the pigeons cried out softly (6)

I believe the answer is:

cooped

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'treated like chickens the pigeons' is the definition.
I can't tell whether this defines the answer.

'cried out softly' is the wordplay.
'cried' becomes 'cooed' (I am not sure about this - if you are sure you should believe this answer much more).
'out' means one lot of letters goes inside another.
'softly' becomes 'p' (short for piano, musical term for softly).
'cooed' placed around 'p' is 'COOPED'.

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I've seen this clue in the Evening Standard.

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