Effect of Nutritional Level While Feeding Paylean to Late-Finishing Swine (1)

Purdue University 2000 Swine Research Report. Over the last ten years, the swine industry has selected to increase percent lean in pigs in response to consumer demand. In search of technology to improve percent lean, Paylean (ractopamine hydrochloride) has been shown to increase carcass leanness while improving growth performance when fed to finishing pigs. It has been documented that average daily gain (ADG) and feed efficiency (F:G) are improved when feeding Paylean to finishing hogs, and these improvements increase as the dose of Paylean is increased when pigs are fed a constant 16% crude protein (CP) diet. It has also been documented that improvements in carcass leanness are also seen, and these improvements increase as the dose of Paylean is increased while feeding a constant 16% CP diet. With todays leaner genetics, with higher lean accretion rates, the question of a 16% CP diet needs to be re-evaluated as being adequate for todays pigs when being fed Paylean. In todays swine industry, most pigs are also being phase fed to improve growth rates, leanness, and cost efficiency. A phase feeding program that would match the projected lean accretion curve expected with Paylean may yield even greater growth and leanness response compared to the old flat 16% CP diets while feeding Paylean. Therefore, a late-finishing study (last six weeks) was conducted to evaluate the effect of feeding a constant dietary protein level or a phase feeding program of varying protein levels, designed to meet the projected lean growth curve (Schinckel et al., 2000), on ADG, average daily feed intake (ADFI), F:G, fat and loin depth, carcass weight, premiums, and percent lean while pigs were being fed Paylean. This trial was conducted over a six-week period from April to May, 2000.