The protein result from the bulk tank is the average of all cows in the herd, weighed on volume. By selling the low-protein cows you will improve the bulk tank result overnight. That’s what makes milk recording such an important tool for farmers selling stock.
While selling cows and replacing them with heifers will reduce production levels, as heifers produce about 70% of a mature cow, it is a good long-term investment. That is of course, if the heifer has a