Broken bones in our Netherland Dwarf babies

Question
Hi Dana
My husband and I bred Netherland dwarf rabbits for some years, but gave up when our children were young as we could not give them the necessary time and attention.  However, now that our children are older we have started breeding again. We have only started recently and our first two rabbits were rescued so we do not really know their background.  In our first litter we got 4 beautiful babies, they all appeared healthy and strong, and they all weaned easily.  We took them away from their mum at 7 weeks and all was going well, until a few days ago when we discovered one of the babies had a broken leg.  We took him to the vet and he has had a splint put on, and he seems to be doing fine, but today when we were checking we noticed another baby also had a broken leg, and it is going to the vet as we speak, but as it is an emergency vet and not our usual vet I thought I would ask your advice to try and find out if this could be something hereditary.  We have checked all the environmental elements of their life and we can't find anything that would cause injury, and the other two babies are fine.  They have a diet of junior/dwarf pellets, and fresh veg and they get to run round the garden every day and are always handled with love and care.  We love our little bunnies very much and we hate to see them suffer even a little, could you please offer us some advice about what this could be and if there is anything we can do to stop it happening again.

Thank you
Jillian

Answer
Dear Jillian,

Well, there are three main hypotheses I can think of here:

1.  There is something cryptic that is causing injury to the babies in their environment.
2.  They have a congenitally weak skeletal system.
3.  Their diet is insufficient in calcium or other nutrient/factor necessary for bone formation.

Babies should get mama's milk for a full 8 weeks, but I would be really surprised if weaning at one week early would cause a deficiency like this.  Are they getting natural sunlight? This is important for calcium metabolism.

What is their diet?  Do they get sufficient calcium?  Phosphorus?

Is it possible that there is a towel or something on which they might be catching their toenails and wrenching their legs?  Even a loose thread can be a hazard.  Check for any opening where a little leg could stick through and break if the bunny is startled and moves suddenly, such as the grid of a playpen.

Finally, you might ask the vet if radiographs of their skeletons would be a good idea, to see if they have unusually fragile/porous bones.  If the parents are closely related to each other, they may have passed on an unfortunate, recessive condition causing such a thing. But I'd think that would be the last thing to check, if all the other ideas don't pan out.

I hope you can get to the bottom of this mystery, and I hope the two little injured ones make a quick recovery.  They can heal very quickly at this age!

Please also see:

http://www.bio.miami.edu/hare/breeding.html

I hope this helps.

Dana

P.S. - If you found this AllExperts answer helpful, please return the favor and help our rabbit rescue by voting for H.A.R.E. in the Shelter Challenge.  It's FREE, but you could help us win $1000 to support the medical care and spay/neuter of our rescued rabbits.

http://tinyurl.com/voteforhare

Enter "hare" as the shelter name and "FL" as the state, and vote!  Please tell all your family and friends!  And thanks a million for the bunnies!