I haven't raised a straight Holstein, but usually raise 1/2 H., half Jersey. The last one I had looked like his mama (H.) and was probably the best beef we've ever had. He was also the fattest, despite not being finished on grain, but we had really good grass last fall. He was 18 months. The only thing I hated about raising him was that he would go thru these wicked growth spurts and look like a rack of bones, even if I grained him. Then he'd fill right back out for a month or so and then repeat the process.
I sure hope it tastes good....I have a big holstein bull calf named Beef on my jersey milk cow, he is growing crazy fast. I am wondering if he is doing these crazy growth spurts and stealing my creamy milk for days at a time. I went from 6 litres per milking to 3 to 4 liters and nothing has changed except my calf keeps getting BIGGER.
I was going to butcher him at the end of fall before his hormones kicked in. I got him mostly as a back up for milking my cow...in case I was not very good at handmilking and to take up the surplus milk. I know there won't be tons of meat on him but essentially it is free meat.
They do have a lot of meat, of course they can get gigantic! Your cuts will be a little different size and have bigger bones, but we have really enjoyed our holsteins. It takes longer to finish them and they do take a lot of groceries but it is very good beef. Ours were over 18 months and averaged 1400 pounds each.