Female on farm uses pitcher mostly (3)
I believe the answer is:
ewe
'female on farm' is the definition.
(female sheep)
'pitcher mostly' is the wordplay.
'pitcher' becomes 'ewer' (synonyms).
'mostly' means to remove the last letter.
'ewer' with its final letter taken away is 'EWE'.
'uses' is the link.
(Other definitions for ewe that I've seen before include "Lamb's mother" , "She'll provide material to knit" , "Female animal" , "Ruminant" , "Wool producer" .)