This question is for breeders of dairy goats reguardless of breed. Occasionally I have seen (and it seems more so in certain lines of Nubians than others) does with a beautiful rear udder but they have fore udders with a nice extension but they shelve when full at 12 hours. How serious of a fault is this? Does it usually improve with age? or does it get worse? or is it a culling factor as a first freshener? Do other breeds experience this or is this a Nubian trait?