Evaluation of Four Ractopamine Use Programs on Pig Growth and Carcass Characteristics

Purdue University 2002 Swine Research Report. Paylean (ractopamine hydrochloride by Ela nco) is a feed additive approved to be fed at levels of 4.5 to 18 grams per ton (5 to 20 ppm) from 150 to 240 lb body weight, increasing growth performance while also increasing carcass leanness. In previous research trials, the ractopamine response began to decline near day 22 when fed at a constant dietary concentration, resulting in decreased growth performance over the remaining duration of the feeding period. Therefore, the objective of this study was to determine the level and timing of Paylean stepup programs to enhance and extend the ractopamine response by increasing the dietary concentration of Paylean. Data collected also provided additional data to model the optimal Paylean use strategy.