I have notice since 4 months they haven't grow much they weight 3 and 4 pounds and they are pure new zealand and they are really healthy everything they do like a healthy bunny but when they were 3 months old they did have a on and off diarrhea and medicine of a antibiotic and a diarrhea stop medicine but since then I haven't seen anything of diarrhea but I don't get why they don't grow