Tightness in the poultry fat market continues to drive fat and grease prices higher in the South through the Eastern markets. Prices for yellow grease and poultry fat moved higher today on limited supply and strong demand. Finding an offer for low acid material has proven challenging for some buyers, with both the feed mill and pet food demand very strong. Broiler slaughter is forecast lower over the next six weeks, averaging 150.5 million head, down 3.2 percent from last year and down 10.3 percent compared to the prior six-week average. Next week’s holiday interruption may provide some pause to the price rally…