Yep splay leg. There are braces you can make (google it) to help put them back in places in not so severe cases, I do not know if one with this bad will work though. Just taking it from the box and back to normal feeding won't be enough, I've done been through it a more than I like to admit. You have to physically put a brace on, or go ahead and cull. I kept a MR to grow completely up to see how well they would do, grew up with frog legs like that, lived for a little over a year. Seemed happy and all, but because of the pressure put on its belly and hips all the time, it had GI issues all the time, the constant contact along with rubbing causing additional infection/problems no matter the bedding used (always was on solid bedding as when I tried to leave on wire he kept getting stuck and scratching his belly trying to get lose)...so he had to be put down.
Some times it because of over feeding with one or few kits, however it can also be caused by nest boxes that are too slick for kits to get a grip with their feet. I had a litter of 9, before I knew to put any thing in the boxes, that all had it. There were all like the kit above, and all had to be terminated. IF I had the extra time and was going to keep, I might try the splinting but they have to be monitored and kept inside with....its just not some thing I want to do. When I find litters that seem to always be fed and aren't able to roll over on their own or move around once hitting a week I remove the box OR add more kits if I can. IF they can't crawl with out slipping all over, I add more stuff to the box so they can. Heavy milkers are good but can be a big pain. I've ONLY had this problem with my MR though. My Hollands tend to be not so great but working on adding that to the culling list, show stock in some lines just doesn't seem to have the milk like others do but that's another topic.
