Check the Conditions Thoroughly Before You Interfere
First off, there are some things you need to check to ensure that the mother has indeed stopped caring for her babies. Below is some advice from a professor at University of Miami Biology Department, Dana Krempels in her article Care and Feeding of Orphaned Domestic Rabbits.
“Unless the mother rabbit is known to be dead, there is a good chance that she is feeding her babies, even if she seems to be ignoring them. A mother rabbit does not constantly tend to her babies the way a mother carnivore does. Rabbit mamas feed their babies only twice per day, and then leave them alone. This is normal and natural: in the wild, a mother rabbit not in the process of feeding her offspring stays as far away from the nest as possible to avoid attracting predators to her babies.
If mama rabbit seems to be "ignoring" her litter, check their condition before you interfere. If the babies' tummies are round and full-looking (you sometimes can see a whitish patch where the milk-filled stomach shows through the thin skin of the belly), they are warm, their skin is a healthy, dark pink, and not overly wrinkled, and they are sleeping calmly in the nest, then mama is feeding them. If the babies are very wrinkled, cold, bluish in color, have shrunken bellies, and perhaps are even crawling around looking for mama (instead of nest-sleeping, as a well-fed baby should), then you may have to intervene."
Next, you will try to encourage the mother to nurse her babies. You do this by holding your rabbit over her babies so they have a chance to nurse. Stroke your rabbit so that she is calm. If the babies have a chance to nurse, this will most likely fix the problem. Just continue to monitor if the babies are getting fed.
If the mother rabbit is very ill, is dead or is being aggressive toward her babies, you will most likely have to remove her and care for the babies on your own.
Feeding Baby Bunnies
Feeding baby bunnies is harder than one may think, the slightest drop of formula inhaled by them can sit in their lungs and give them fatal pneumonia within a few hours. Along with feeding baby bunnies, you also have to groom and stimulate their bodies so that they go to the bathroom. Many newborn animals cannot urinate/defecate on their own. The mother rabbit often helps in the process when she grooms them.
If you’re still up for the adventure of raising a baby bunny without the help of its real mom, I suggest you read the rest of the article mentioned above, “Care and Feeding of Orphaned Domestic Rabbits.” It goes into detail about how to really take care of a baby rabbit, feeding, bathroom issues and weaning included! You can also download our eBook Human's Guide to Feeding Baby Bunnies to find what formula to give your baby bunnies.
Seek Professional Help
If you do not know how to care for baby bunnies and do not feel confident in your ability to do so, please do not attempt to feed them. Taking care of a baby bunny is complicated and there are a lot of things that can go wrong. Feeding them too much milk, not making them go to the bathroom or having them sleep at the wrong temperature can result in them becoming very sick or not making it. There are many aspects that can lead to things going wrong with baby bunny care.
We know you are just trying to do the right thing and trying to care for a baby bunny since its mom won’t, but make sure you consider all of the factors. Please do all your research!
The Number One Question We Get Asked + Our Answer
Q. What do I do when the mother is not feeding them or treating them differently?
A. Feeding baby rabbits or just a single baby rabbit (kit) can be a very tricky thing enterprise and if keeping them alive is important then a lot of support and knowledge will be required. We are not experts in this area which is why we stress that you contact your veterinarian. They are best ones for the job of helping you keep your kits alive.
With that being said, here are 3 different resources you can use.
We created an eBook titled "Humans Guide to Feeding Baby Rabbits" that walks you through the steps you need to take if the mother rabbit is no longer feeding her babies. It talks about the two different options you have, the way to feed them, the ingredients you need to feed them, etc. You can download it here or click on the image below.
You can also read through this article that talks about the ins and outs of doing it, it was written by some very trustworthy and quality people: http://www.bio.miami.edu/hare/orphan.html.
Here is another excellent blog by Rabbit.org on the subject: https://rabbit.org/care/babies.html