dairy cattle vs milcher

dairy cattle and milcher both are nouns.

Word	Noun	Adjective	Verb	Adverb
dairy cattle	Yes	No	No	No
milcher	Yes	No	No	No

As nouns, dairy cattle and milcher are synonyms defined as:

Other synonyms of dairy cattle include dairy cow, milch cow, milk cow, milker.

dairy cattle (noun)	milcher (noun)
cattle that are reared for their milk	cattle that are reared for their milk