To pick up on the antinutrient thread, though this is about the foliage and not the seeds: I fed my rabbit herd large quantities of caragana leaves and stems run through a chipper over a period of about six months. They were clearly highly palatable because the rabbits ate them enthusiastically in preference to the grass hay that was always available. Young rabbits grew well on this diet. The downside was that there were no births after the first month of feeding caragana foliage. Either conception was prevented or litters were aborted very early in development leaving no trace in the enclosure.
Conclusion: I would only feed caragana to young rabbits being grown out for meat. I wouldn't feed any again to breeding stock, or feed it as tree hay (which had originally been my intention).
