And milking machines were first patented in 1879, so it's not like it should be news to any dairy farmer anywhere in the world.
Even with milking machines, it takes one worker over an hour to milk 40 cows. 600 cows would require 15 helpers.
Each cow needs to be swabbed with a sanitary solution, then the machine applied, later removed, that cows space cleared and another brought in. Wiyh care, mucking out, and feeding Etc., the dairy business is still labor intensive. However, nowhere is it stated that labor need be illegals or aliens. Pay a decent wage and citizens will do it.