Greetings from the front range in Colorado @Teresa40 and welcome to BYH! When you have a question to ask it's really better if you open a brand new discussion, or add it to an "active" thread... The last entry to this thread was over 3 and a half years ago I believe there are several threads that talk about this issue, but I can't recollect which ones . I think this might discuss what you're asking about: http://www.backyardherds.com/threads/vaccinations-protocols.33636/#post-427802 This is the most recent thread.
Anyway, I'll tag a couple of cattle folks who can probably steer you right (pun intended ) in case that doesn't work for you. Mean time... Browse around You'll be surprised at how much info and experience is shared in the threads!