[header] How to feed deer [title] Introduce deer to a new diet slowly. [step] It takes deer take 2-4 weeks to adjust to a new diet, so start feeding them gradually. Slowly introducing new types of food into a deer's diet will help their digestive system learn to process it. 
Deer typically eat woody vegetation that is found in forests, so feeding them foods that are rich in fats and carbohydrates can be extremely harmful. [substeps] Begin introducing new foods by combining supplemental foods with deer's natural diet.