I have a mare I bought in Oct which is also pregnant unknown to me, bred in may I think. My friend who owned her said I was to cut her food back a lot until she has the baby, my vet said to keep it the same and my mare is doing good so far. My friend was over yesterday and still wants me to cut it (she's bred her 2 times before) more but I'm following my vets advise. As long as she is not showing any fat and her heartgirth stays about the same, I was told she's good, you don't want the baby to get too big too fast, hope this helps.
Many people have sighed for the 'good old days' and regretted the 'passing of the horse,' but today, when only those who like horses own them, it is a far better time for horses. ~C.W. Anderson