Bags in stock, those remaining for one with a blocked nose? (6)

I believe the answer is:

udders

'bags in stock' is the definition.
(stock can mean farm animals)

I can't explain the rest of the clue.

(Other definitions for udders that I've seen before include "Milk producers" , "These full of milk" , "de rest" , "Cows' teats" , "Containers for milk, naturally!" .)

I've seen this clue in The Guardian.

Want a hint initially instead of a full solution? Install my app