Fl6-Lancaster Farming, Saturday, January 5,1991 PI Pork Prose HB y Penn State Extension Swine Specialist Dr. Kenneth B. Kephart With the recent drop in soybean prices, hog producers are again checking the economics of using soybeans (raw or roasted) rather than soybean meal in swine rations. Let’s take a brief look at the feasibility of using the soybean for hogs. Much of the information below is taken from a recent review by Herkelman and Crom well (“Feedstuffs,” 1990, 62(52): 13). Raw Soybeans Raw soybeans contain a number of compounds that interrupt the digestion and absorption of nutri ents in the pig. The most signific ant of these compounds is trypsin inhibitor which limits protein digestion. Feeding raw soybeans will depress growth rate and feed effi ciency. In starter pigs, growth rate is reduced by about 50 percent (.61 vs. 1.23 Ib./day), while feed effi ciency is decreased by approxi- EB-g- GflAtemnmre anmip 2388 Old Leacock Rd., Gordonville, PA 17529 CUSTOM BUILT STOVES, WOOD OR COAL HIGH PRESSURE WASHERS HIGH-TENSILE FENCING -A PEQUEA & PEERLESS BATTERIES Klftilfiflll DISTRIBUTOR FOR BEARINGS k-‘. n . ’ SPROCKETS, PULLEYS. BELTS KENDALL & DRYDENE OILS & LUBRICANTS J igjfr a & Egg UFSSeHiu by Kenneth B. Kephart matcly 40 percent (3.58 vs. 2.12 lb. fced/lb. gain). In grower-finisher pigs, the reduction in both growth rale and feed efficiency is less severe. Weight gains are impaired by 22 percent (1.38 vs. 1.78 Ib./day) and feed efficiency is depressed by 19 percent (4.07 vs. 3.43 lb. feed/lb. gain). In the early 19305, research at the University of Nebraska showed that feeding raw soybeans to sows in both gestation and lac tation had no deleterious effects. Their research included studies from sows over the course of three parities (litters). However, more recent studies suggest what some nutritionists have suspected - that raw soybeans may limit milk pro duction and baby pig survival. A summary of three studies in which raw soybeans (or soybean meal) were fed during both gestation and lactation is shown below. EFFECT OF RAW SOYBEANS ON Soybean Pigs Pigs Source Born Weaned SB meal 9.3 8.5 SB meal+ oil 9.5 8.6 * Summary of three separate studies. As the table shows, piglet birth weights are somev. hat higher from sows consuming raw soybeans during gestation. In the raw soy bean group, survival rate of the baby pigs and weaning weights are slightly less. This is apparently due to a reduction in feed intake during lactation. The drop in feed intake also leads to higher sow weight loss during lactation (data not shown). Low Trypsin Inhibitor Soybeans Research with low trypsin inhi bitor varieties of soybeans have been conducted at several univer sities. There is no question that these new varieties are superior to conventional soybeans when fed in the raw state. However, reductions in growth and feed conversion still occur in starter, grower, and finisher MILK. IT DOES A BODY GOOD. MIDDLE ATLANTIC MILK MARKETING ASSOCIATION, INC. The only concrete slat with Your Animals Comfort In Mind r K\ 477 East Farmersville Rd. EYSTONE > New Holland, PA 17557 CONCRETE f (717) 355-2361 PRODUCTS SOW PERFORMANCE* Weaning Survival, Wt., Lb. % 12.2 91.4 11.2 90.5 phases if the low trypsin inhibitor varieties are not cooked. Soybean Processing Soybeans can be roasted or extruded. In the roasting process, soybeans reach 230-260 degrees F 2-5 minutes after reaching the roaster. In an extruder, soybeans are forced through small holes, causing the soybean material to reach 300 degrees F in less than 30 seconds. Which process is better? Both methods destroy the growth inhi bitors. However, extrusion pro cess ruptures the oil cells, which, according to some nutritionists, may improve oil digestibility. And in fact the oil cell mpture does increase oil utilization in the chick. Whether the same response occurs in the pig is less clear since few direct experiments have been “Waffle Cattle Slats” Waffle Heifer Slats H-Bunks Contact Us For Complete Details On Heifer Cattle, Hog And Free Stall Barns ■MC. conducted to answer this question. However, there have been a lot of indirect experiments to suggest that oil from ruptured cells is superior to that of oil from intact cells in the soybean. Herkelman and Cromwell looked at experi ments conducted over the last 30 years. Using roasted soybeans increased growth mtes by about 2 percent and improved feed effi ciency by about 5 percent over that of soybean meal. But researchers have, on the average, found that adding oil to a conventional com-soybean meal diet also increased weight gains by 2 percent, but improved feed conversion by more than 8 per cent. Effect Of Soybeans On Carcass Quality In experiments conducted since 1969, cooked soybeans in growing-finishing diets increased backfat by about 4 percent (1.29 vs. 1.24. inches) and decreased loin eye areas by roughly 3 per cent (4.58 vs. 4.72 sq. inches). Waffle Hog Slats Concrete Hog Penning I 39” Formerly Syri-Con Precast Corp. J-Bunks