Things You'll Need
Water bottle or water bowl
Timothy hay-based pellets
Alfalfa hay-based pellets
While most pet rabbit diets are geared toward preventing obesity, there are some rabbits that might need an increase in nutrients. Rabbits that are recovering from an illness, or that have been rescued from neglectful situations may need to put on some weight.
Take your rabbit to the veterinarian. It is important to ensure that your rabbit is free of parasites or other medical issues that might be causing continued weight loss. Also speak with your veterinarian about medication that can enhance your rabbit's appetite and foods the veterinarian can suggest for weight gain.
Install a water bottle or water bowl in the rabbit's cage. While all rabbits need to have fresh, clean water available at all times, skinny rabbits may be especially dehydrated. Watch the water levels closely and keep the water source full at all times.
Provide fresh Timothy hay, or mixed hay, which might include a bit of alfalfa hay, in your rabbit's enclosure. Alfalfa hay is rich in calcium and protein, but it isn't recommended for regular feeding because it can cause bladder issues in rabbits. Also offer pelleted food to your bunny to round out his diet. Pellets are made of hay fortified with nutrients. Offering a balance of quality hay and quality pellets is what a growing bunny needs.
Give your rabbits a treat of fresh vegetables every day. Wheat grass, carrot tops, collard greens, parsley and radish tops are just a few veggies your rabbit can munch on. Avoid feeding too much kale. Fruit should be fed to bunnies sparingly. One to 2 tablespoon of fresh fruit for every 5 pounds of body weight is all she needs. Some acceptable fruits include pears, kiwis, strawberries, apples, pineapples and melons.
Weigh your rabbit on a scale every week. This helps you chart your progress and it also lets you know when your rabbit has reached an acceptable weight.
Avoid feeding your rabbit grains, refined sugar or beans, even if you are trying to fatten them up. While a rabbit will plump up on a diet including these foods, they can also develop a gastrointestinal disease.
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