So, I have been successfully tractoring some New Zealand Whites all summer and they have adapted to this diet very well. But I'm almost out of ground to move them over. Last year I had a couple rabbits that I tried tractoring over ground that they had been on over a month before. Both rabbits developed wry neck and died within 24 hours. It was suggested that this happened because I ran them over ground they had been on earlier that year, and they you need to wait a full year before using the same ground a second time. Does anyone have any experience with this? How long does ground need to sit before running rabbits over it a second time? Is it a winter freeze needing to kill of some nasties or something kind of a situation?