Patrick thank you so much for the information. I really appreciate your take on this.
So here is what I think I am understanding (from this and other threads).
Jersies are predisposed to this problem (and are also more difficult to keep in good condition).
Don't feed anything but grass/pasture.
Adam says Alfalfa is fine except for the last week or so of the pregnancy. Am I right that you are saying not to feed alfalfa at all when they are dry? If so does it change anything that I dried her up before she was bred. (I had trouble finding an AI guy and since she had been milking over a year we decided to give her a break.) So would you still say no Alfalfa for this whole pregnancy?
Are there specific breeds that are your recommendation as to hardiness?
Thank you also for the links. I can see that I have another skill to learn.