It's inaccurate to say they can't stand and that they die by 10wks. If you keep them in a confined space where they don't get to forage at all and you feed them heavily then it is possible for those things to be true. However, if you raise them as many people do in their backyards, they don't have leg problems and can live far beyond 10wks. Ours never live longer than that because we raise them to be butchered at 8 or 9wks, not because they all keel over. We rarely have one with leg problems though it does happen sometimes and the instance off flip (heart failure), is exceedingly low.