Sounds like these dairy farmers aren’t doing well at having good working conditions or pay for their employees. Pay a decent wage and have good working conditions/benefits and people will take the job and retaining them will be easy.
Doesn't matter what they pay, locals don't want to do the hard all weather work involved. Dairy farming is not seasonal like growing things although it involves field work as well. Trades pay really well but there is a shortage of tradespeople because physical work is no longer in style. Farmers are a business like anything else, they have to operate within their revenues. Things like feed prices are going through the roof and the increases in milk prices aren't keeping up with the farm costs.