Production? Define production? Maximum liters per cow? And do your clients honestly discuss with you there farm accounts?I can only speak for the herds I work with, but out of my 10 best herds (in terms of animal health, production, profit) 9/10 milk record and the other one doesn't because it would be too costly in the parlour. Of my 10 worst herds 2 of them milk record.
It's basic cow management information, along with calving, inseminations, PD etc.