How would feed affect it?
Housing was KW cages 14g floor 1/2x1 inch for the first 10 weeks, then he was separated from his sisters and mom and placed in a tractor on the grass (which allowed him to start digging holes).
Parents and sisters have normal feet. His paternal grandparents had normal feet, but cannot speak for the maternal grandparents.
Like
@tambayo I might consider
not keeping him for breeding. But since you don't know and probably won't be able to figure out what caused this, and he's the only alternative to an ornery buck, it would be hard for me to make a firm determination about how to proceed.
One thing you might check is to see if he has sore feet, which many Rex can develop, and could cause him to hold his feet in a stange position, and walk strangely.
Bent limbs can be the result of a nutritional deficiency. However, if his sibs don't have the same issue, I wouldn't think it was a feed issue. If it resulted from a nutritional deficiency, this particular rabbit could have a higher need for or an inability to process some nutrient(s) compared to other rabbits, which isn't something I'd want to perpetuate.
If it's a bone or soft tissue malformation issue due to his genetic makeup, it would not necessarily show up in his sibs or parents; he could be the only one to show it. Many characteristics result from the combination of many different genes (known as polygenic traits), so the chance may be slight that you'll see it again, in his offspring or even from the same pairing that produced him.
Even if the trait is based on a single recessive allele (aka simple Mendelian inheritance), that allele needs to be contributed by each parent, which might only happen in one kit in a litter. But if it's genetic, especially if it's due to simple Mendelian inheritance, the problem might start showing up more often if you breed this buck, especially if you breed him with a relative or other individual that also carries the allele/alleles that are behind it.
Another thought that occurs to me is that it might be due to some sort of injury, whether in utero, during birth, in the nest box, or at some later point. This seems the least likely to me, since both front legs are affected, but it's within the realm of possibility. Maybe he was squashed in a less-than-ideal position in utero, or was delivered in a poor position, or was constantly pushed into a corner by the other kits in the nest box. If it was an injury unrelated to the kit himself, IMO it would not be necessary to cull him. But even if it was an injury, there is the chance that he has some inherent (genetic) predisposition to sustain such an injury, which is a weakness you would not want to perpetuate.
If it's a choice between a possible genetic defect versus nasty attitude, I might actually lean toward going with a possible genetic defect, which I would just be vigilant about culling, going forward. (I
really don't like unpleasant animals.) Either buck could pass on his negative trait(s); is it possible to keep the original buck while your young buck proves himself? At 16 weeks, he's getting pretty close to when he can sire his own kits. You could see if he produces kits with this or other problems, or not.
