The question is asked as to whether, if a mother has never had rotavirus,
would her milk still carry the antibodies?
  The "diathelic immune response" as I understand it:  If her baby has been
exposed to the virus and he nurses, he introduces the virus to her, and the
antibody to that virus is produced *on site* at the breast and given to the
baby by breastfeeding.  The antibodies to that virus would not appear in the
mother's blood (plasma?), but they would appear in her milk thus helping the
baby to fight off the illness.  Baby still might get sick, or he might be able
to fight that bug off completely thanks to mom's milk.
  This benefit of breastfeeding is one of my favorites.  It is the one that I
mention most often to mothers who have their breastfed babies in daycare-
where often the baby is exposed, but not the mother, to any given "bug".
Mothers who only bottlefeed breastmilk (baby never nurses at the breast) will
miss out on this very important aspect of the immunity-building properties of
human milk.

Lisa Jones, LLLL in Wellington FL- 1/2 hour north of Boca Raton