Feeding baby rabbits falls mostly to the mother rabbit for the first 3 weeks of the bunny’s life. Between 3 weeks and around 6 weeks old, the baby rabbits need less and less of mom, and more and more pellets and hay.
At the point they no longer "need" the mother for food, they are said to be weaned. This physiological point arrives almost precisely at 4 weeks of age, at least in regards to the operative word "need." This means that a kit orphaned for some reason at 3.5 - 4 weeks old can go straight to solids, and will not need supplemental milk unless it happens to also be malnourished.
In our domestic rabbits, however, the doe permits her kits to keep right on nursing, simply because she can physically afford to do so. The typical litter of bunnies in your home or hutch can be 6-7 weeks of age, possibly older, by the time their mums forbid any more nursing.
See our Raising
Baby Rabbits page for more detail on the normal care of bunnies from 2 weeks of age and older, including the processes of weaning the litter.
What do you do if something catastrophic happens to the doe?
Every once in a while tragedy strikes. The doe could develop young doe syndrome. You’d find her suddenly dead in her cage, with her kits being just a week or 10 days old. Or, the doe could develop mastitis, refuse to nurse the kits because of the pain, or herself die from bacterial toxins.
Whatever the disaster, feeding baby rabbits now falls to the rabbit owner.
What you do will likely depend on how old the kits are. Obviously, the older, the better the survival rate.
Between the age of 0 to about a week, fostering is
fairly easy, especially if the kits are within a couple days of the age of the
foster-mother’s kits. Just slip the
babies into the new doe’s nest. Do it in
the morning, and rub their little bodies gently with the new doe’s fur in order
to transfer her smell to them.
As you replace the nestbox, give the new doe a generous helping of calf manna, whole oats, or a favorite treat, in order to distract her. She’ll think everything is fine, and by evening, all the kits should smell like they belong in the nest. If you’re still nervous about the doe, just leave the nestbox outside the nest all day, and then put it back in with the doe about suppertime.
The foster doe will do a much better job at feeding baby rabbits than you could, if you don’t overwhelm the new doe with a dozen bunnies. How many kits you give her may depend on her ability to make the additional milk. Adding a source of fats, like whole oats or black oil sunflower seeds, will definitely help her augment her milk supply.
You can attempt bottlefeeding. Here’s some tips and techniques, depending on the age of the orphaned kits.
But first, a sober head’s up: Without careful attention to the bunnies' dietary needs, the survival rate for bottle-fed infant bunnies can be as low as 0 - 10%, especially if the babies are orphaned before their eyes open. That means 9 out of 10 (or worse) often don’t survive. There are a number of reasons bunnies fail to survive without their mums. Here are the most common reasons:
Lou Rea Kenyon, a registered nurse and a licensed wildlife rehabilitation expert, has successfully saved bunny-lives for over 17 years. She is the owner of Nutkin’s Nest Wildlife Rehabilitation Center.
This is where we would send you directly to her wild-cottontail-feeding
protocols, however her website has disappeared from the web.
With her permission however, we summarized Ms. Kenyon's
instructions on our Feeding
Wild Rabbits page, because her instructions for feeding
baby rabbits work for both cottontails and orphan domestic rabbit bunnies.
We recommend Goat's Milk Esbilac, or Esbilac Milk Replacer for Puppies. Whatever formula you use to hand-feed bunnies, it will still need the addition of fat. The easiest way to do this is to use heavy cream.
Bene-Bac (or healthy cecotropes) will be another essential ingredient of the milk formula in order to prevent fatal diarrhea.
See Feeding Wild Rabbits for the formulas and details, including some suggestions should you have been surprised by the sudden death of a doe, and not have on hand any formula.
Good luck with feeding baby rabbits!
By three weeks old, baby rabbits are already nibbling pellets and hay, but they still need mother's milk. They may also still be at risk for life-threatening bunny diarrhea. Nevertheless, their survival rate improves dramatically by 3.5 weeks old, even on just excellent rabbit pellets and water.