University of Nebraska researchers completed two experiments to study the effect of extruded/expelled soybean meal (ESBM) on growth performance of pigs.

ESBM is produced by mechanical friction creating a high temperature for a short time period. The quality and nutritional value is affected by this production method. The final product has about 7% fat, compared with less than 1% fat in conventional soybean meal.

The first experiment was a 28-day nursery trial in which 480 crossbred pigs were housed in an environmentally controlled nursery. They were weaned at 11 to 14 days and averaged 9.05 lb. Pigs were assigned 20/pen, 10 barrows and 10 gilts.

Diets contained either conventional or ESBM and contained similar percentages of digestible lysine.

Two feeding phases were used. Phase 1 diets were fed from day 0 to 14 days and phase 2 from day 14 to 28 days. Pig and feeder weights were recorded weekly and blood samples were collected on days 0, 14 and 28 for urea nitrogen analysis.


Pigs fed the conventional SBM diet had better average daily gain (ADG) and average daily feed intake (ADFI) than the pigs fed the ESBM diet.

On days 14 and 28, plasma urea concentrations were greater for pigs fed the ESBM diet.

In the second experiment, 240 pigs from experiment 1 were selected to continue in the grow-finish phase of the study.

One hundred twenty pigs, each from the ESBM and control groups, were housed in a modified open-front building with 10 pigs/pen (5 barrows and 5 gilts.) They were assigned to either ESBM or control diets, creating four possible diet combinations: control-control, control-ESBM, ESBM-control or ESBM-ESBM.

Diets were formulated on an equal lysine basis. Three phases were used from 0 to 56 days, 56 to 91 days and 91 to 119 days. Diets contained 1.0%, 0.78% and 0.67% lysine, respectively.

Pigs and feeders were weighed every two weeks and blood samples were collected on Days 56, 91 and 119. On Day 119, real-time ultrasound was used to measure longissimus muscle area and backfat. TOBEC (total body electrical conductivity) measurements were collected at the slaughter facility.

ADG was greater for control pigs throughout the experiment. ADG was 1.52 for the control pigs and 1.47 for the ESBM pigs. ADG/ADFI was 1.00 versus 0.98, respectively.

Researchers found no differences in backfat and longissimus muscle area. Hot carcass weight and total pounds of primal cuts were greater for the control pigs.

Researchers: Andrea Tucker, Phillip Miller, Austin Lewis and Duane Reese, University of Nebraska. Phone Miller at (402) 472-6421 or e-mail