One of the metrics we’ve been watching as a sign of herd rebuilding is the number of heifers as a percent of on feed inventory. However, we’re in new territory. For the first time since heifer on feed reporting began in 1996, the inventory of replacement heifers has fallen below Heifers on Feed inventory. Even during the tightest inventory levels in 2013, the gap was more than 1.3 million head greater for replacement heifers.   There are a number of factors that can help explain this other than tight cattle supplies and drought in the U.S. leading to herd liquidation. First is the supply of cattle coming from Mexico. That supply was interrupted by the discovery of New World Screwworm in November. Between late November and t...