Livestock dressed weights have experienced significant trends and volatility which affect wholesale production of red meats. An econometric model was used to estimate the impact of relative prices and technology on cattle and hog average dressed weights. For fed steers and heifers, the economic incentives affecting placement weights and weight added in feedlots were considered. Results indicate quarterly dressed weights of steers and heifers respond to contemporaneous profitability ratios and to lagged feeder prices, the effects being highly inelastic. Cow dressed weights also responded while hog dressed weights did not respond to profitability ratios. Technology changes may have accounted for about 83% of dressed weight growth for steers and about 62% for hogs from 1980-97.