Research Update: Feeding high levels of DDGS to Grow-Finish Swine

by 5m Editor
28 May 2007, at 12:00am

By Mark Whitney, PhD, University of Minnesota Extension. With increased corn costs, there is significant interest in identifying alternative solutions to reduce feed cost and stretch corn supplies.

Distiller’s dried grains with solubles (DDGS) are an obvious alternative to consider, with their increased supply. But how does feeding DDGS affect growth performance and carcass parameters, and what levels can be included in diets? Recently reported data from several groups provides some insight into the corn/DDGS dilemma.

A grow-finish trial recently completed by JBS United (Gaines et al., 2007) indicates that high levels of DDGS can be fed to pigs without negatively affecting growth, although some carcass parameters may be affected. Feeding 30% DDGS diets to pigs from 97 – 284 lbs (5 phases) resulted in similar performance (growth rate and feed intake) to feeding control corn-soybean meal diets, while gain/feed was in fact improved 2.5% with DDGS inclusion. Although carcass weight and fat depth were unaffected, carcass yield dropped from 76.9% to 76.0% and carcass % lean dropped from 54.9% to 54.5% when the 30% DDGS diets were fed. Two nursery growth trials have also been reported by this same group (Spencer et al., 2007) with similar trends in performance. For the first nursery trial (6 week period, 4 phase feeding program), feeding up to 15% DDGS as early as phase II improved gain/feed by 2% with negligible effects on growth rate or feed intake. In the second nursery trial, feeding 30% DDGS to 20 lb pigs for 3 weeks resulted in an 8% improvement in G/F

Recent data reported by University of Illinois swine researchers (Widmer et al., 2007) provides further validation that high quality DDGS, when properly included in growing pig diets, can provide similar or improved performance. Feeding 10 or 20% DDGS to growing-finishing pigs resulted in numerical increases in average daily growth rate (↑ 3%) and feed intake (↑ 4%), while having minimal effects on feed conversion. Pigs were 5 lbs heavier at market and had 4 lbs greater hot carcass weight. Backfat thickness was unaffected, although belly thickness decreased with increasing DDGS level, but belly firmness was unaffected. Dressing % and carcass lean % were also similar among dietary treatment groups.

The most recent research coming from the University of Minnesota swine research group (Xu et al., 2007) indicates similar findings to the previous 2 groups. Including 10, 20, or 30% DDGS in grow-finish diets resulted in similar growth rate. Feed intake was reduced at the 20 and 30% DDGS levels, but also resulted in improved feed conversion. Including 10% DDGS had no effect on carcass quality, but including 20 or 30% DDGS resulted in carcass quality differences. Dressing % was reduced, as was belly firmness, but no differences in % lean were observed.

These trial results indicate that, when properly included, good quality DDGS can be successfully included in grow-finish diets at levels up to 20 or 30% without negatively affecting growth performance. At these higher inclusion levels, however, caution needs to be applied that potential decreases in dressing % and/or carcass % lean are accounted for. For instance, if we assume a 1% decrease in dressing % when feeding 20% DDGS, this results in about a 1.3% drop in carcass weight sold, assuming a similar live body weight at the time of market. At $60/cwt carcass basis, this is a loss of $1.62 for a 270 lb live pig. Using these assumptions, one can conservatively price in DDGS, then evaluate slaughter sheets later on to see if there is in fact any drop in dressing %.

May 2007