You can use a plastic or rubber hot water bottle and wrap a fleece blankie around it. There are special heatpads for small pets called Snuggle Safe that vets use. You can use a normal PET bottle with not so hot water in it and wrap a fleece blankie around it. You can also sit the bunny in your lap and wrap him in a fleece blankie and try to warm him up with your own body-heat. Sometimes that’s comforting to a bunny, to be close another living being.

It really is super-important that you keep him warm now. Bunnies tend to get hypothermic when they’re unwell and that worsens the problem. Is this a very young bunny?

How is he doing now?

If its been two rabbits from the same breeder, it leads me to believe that something was wrong with them genetically. Does the breeder know this happened to you twice? They may not know they are carrying and selling sick rabbits

(((((binky free little bun!)))))

I’m so sorry to hear this. This is unfortunately not super-uncommon in very young rabbits and it’s not something you did, and it is REALLY difficult and requires both good care and lots of good luck to save a very young bunny that has come down with diarrhea. 

If you want to read about this, here’s a good article by Dana Krempels, a biologist who is like THE expert on bunny health: 

Loose stools baby bun
Scroll to “Runny Stools: When things go wrong”. 
Coccidosis, caused by a micro-organism, that D Krempels mention at the end of the section, is not uncommon in rabbits from rabbitries. I would not rule out the possibility that the breeder has this problem in his/her rabbitry. It’s difficult to get rid of. I’d recommend you choose another breeder or adopt a more mature bunny, if you want to open your home to another bun. (This is perhaps not sth you want to think about now, so close after this tragic event.) 

If you adopt a more mature rabbit, it’s unlikely you’ll have to go through this again, because true diarrhea is as a rule a disease of the very young. 

Thank you for taking this bun to the ER vet and for doing all you could for him. 

Oh Im so sorry you’ve had to go through this again. How sad! ***Binky free Toby***

Just further on intestinal coccidia; it is sometimes a practice of rabbitries to give medicated water or feed containing anti coccidials. These may help infection remain subclinical but not eradicate it completely. Then once a young rabbit leaves, the parasite can reach a level where it will cause intestinal disease. 

If you are thinking in the future to welcome another rabbit into your home, do consider an adult from a rescue if you have one close by. They can be a lovely temperament and usually are already desexed and health checked. There are sometimes junior rabbits available too. : )
Something to consider when the time is right. Again, I’m sorry for your loss.

I’m very sorry for your loss.

(((((Binky Free))))))