I have never seen anything to feed the animals with at the petting area. We have been there 4-5 times and have never been able to feed them. My kids would have loved it (who am I kidding, my DH would have knocked my kids down to get to feed the animals!!!).
I think you can brush them, pet them etc. but the feeding is strictly controlled for health reasons etc. of the animals and as such feed is not provided for the guests