Could happen just as easily in a Holstein bull as in a Holstein cow or just as easily as in a beef cow. It's fairly common in dairy herds though. I haven't dealt with it yet. What symptoms are you seeing?
I took him into the vet because he was losing wieght, looked like crap. The vet said he thought it was leukemia, did say it could be a severe case of worms. I'm hoping for the worms, said it would be 2 months if it was worms befor he started looking better.