The milk is healthier to drink if the animals never get any grain.
The seeds in green grass contain enzyme inhibitors, so that they are not digested, while dry grains have very little inhibitor, and thus get digested. This means that the milk will be low or bereft of omega3, and CLA if they get grain.
goat milk is a little to sweet for my taste. Had to try it once during kidding season...my bottle baby sucked down 2 8 oz baby bottles real quick...had a gal in the area that raised milk goats and I bought my baby’s milk from her.