It's been a while since the Yonder has caught up with the controversy over animal ID. Remember the National Animal Identification System (NAIS) — and if you don't there are stories here and here — the regulations that would require every piece of livestock to have its very own number? The US Department of Agriculture said it would help track disease; ranchers and farmers said NAIS would create an unholy mess for many producers.The use of animal ID numbers had been voluntary. But on September 22, the USDA issued a memorandum that would make NAIS mandatory for most producers.   R-CALF USA, a cattle producer group, wrote USDA (and several members of congress) this week protesting the memo. R-CALF contends the USDA violated federal administrative procedures because the agency failed to post notice of its intentions or consider public comments on the rule-making. Opposition to the NAIS is strong in some quarters, as this opinion piece demonstrates.