My understanding (sorry no references, I probably picked it up from farming background) is that animals like cows, sheep etc. do not pass immunities through the placenta - therefore their young are far more vulnerable at birth than human babies - and the immunological protection of colostrum is vital in the truest sense of the word. Mary Broadfoot, Paisley, Scotland [log in to unmask] The Breastfeeding Network - Independent Support and Information about Breastfeeding http://webzone1.co.uk/www/cathus/bfnindex.htm