Is it recommended to keep the baby on a formula for longer and delay introduction of cow's milk if there is known history of lactose intolerance in the family?

Better to stay on the safe side and check with your PD when your baby can start on cow's milk based on his and your family's medical history. Aside from lactose intolerance, there are other risks like iron deficiency anemia. See them here: http://wholesomebabyfood.momtastic.com/milkforbaby.htm