Date of this Version
Paylean® is a feed additive that improves feed efficiency, daily gain and carcass merit in finishing pigs. Restrictions in space allocation are known to reduce daily feed intake and daily gain. Thus, pigs may not respond as expected to dietary additions of Paylean® if feed intake is reduced due to crowding. A 2 x 2 factorial design was used to examine the potential interaction of Paylean® and space allocation. Experimental treatments were: 1)14 or 19 pigs per pen (8.0 vs 5.9 ft2/pig); and 2) Paylean® for four weeks prior to slaughter (0 or 9 g/T). In this experiment, there were no interactions between space allocation and dietary Paylean® additions for overall daily gain, daily feed intake, feed conversion, carcass weight, carcass yield, carcass merit, carcass fat free lean, or daily fat free lean gain. Crowded pigs grew slower with no difference in feed conversion efficiency versus the uncrowded treatment. Pigs fed 9 g/T Paylean® for four weeks prior to slaughter had no difference in daily gain or final weight, but did have an increase in carcass yield (75.3 vs 74.6%), loin depth (2.71 vs 2.64 in.), carcass percent lean (56.0 vs. 55.5%), and carcass premium ($5.99 vs. $5.54/cwt) versus those fed 0 g/T. Incidence of and severity of tail biting were recorded on day 86 and there were no differences due to space allocation or Paylean® addition. These results suggest the response to dietary Paylean® additions is independent of the response to space allocation. In addition, the lack of treatment effects on tail biting score on day 86 suggests neither space allocations nor dietary Paylean® addition were the cause of the tail biting observed in this experiment.