This is a list I've compiled from my own experiences and from email from other breastfeeding moms over the past few years. My son hated those brown latex nipples for some reason. He would tolerate the Nuks but really preferred the Avents. Make sure whatever kind of nipple you choose has a single hole rather than multiple holes so that the flow is slow.
Many babies are uncomfortable if the milk flows too fast.
They may choke and refuse the nipple again. Sometimes, after the baby realizes she's getting some nice, warm, familiar Mommy milk, she'll latch onto the bottle. Sometimes, after baby gets accustomed to taking milk from a source other than Mama's breast, she'll adapt to a bottle. Have the caregivers try a sippy cup, just dribbling small amounts of milk into baby's mouth. Be sure the caregivers are heating the milk enough but not too much.