Full Fat Soybeans in Swine Rations

Mike Yacentiuk, Swine Specialist, Carman

In 2000, Manitoba farmers seeded over 18,000 acres to soybeans. It is expected that in 2001 soybean acreage will increase. Most of Manitoba’s soybeans are sold to US crushers for oil extraction. Some soybeans remain in Manitoba and are heat-treated and used as animal feed.

Soybean meal, the by-product of the oil extraction industry is the single largest source of supplemental protein used in livestock feeds in North America.

Soybeans should be cooked before they are used in all swine diets where efficient growth gain is the object. Raw soybeans have chemical properties that make them difficult for pigs to digest. Properly cooking the soybeans by either dry roasting, micronization or extrusion produces an acceptable protein source for swine. Roasting can be done on-farm.

Cooked full-fat soybeans cannot replace soy meal on a pound-for-pound basis because they contain less protein and lysine than soybean meal, while containing more fat and energy. Because of the high fat content (18%), heat-treated whole soybeans offer a convenient alternative to adding liquid fat to swine diets, especially in on-farm mixing situations.

Processed soybeans can be used in a variety of swine rations. Ground, roasted soybeans can be incorporated into starter pig rations. However, the results may vary and there may not be any improvement compared to starter pigs fed with soy meal. Extruded soybeans exhibit more consistent pig performance results than roasted beans in starter diets.

Lactating sows benefit from the increase in energy density provided by rations containing added fat. Grower and finisher hogs fed rations containing ground full-fat soybeans exhibit slight improvements in gain and feed efficiency as compared to typical rations.

Full-fat soybeans fed at high levels may cause deterioration of carcass and meat quality, especially in hogs fed corn-based rations. It is therefore advised to limit full fat soybean usage in finishing hog diets to 10 per cent of corn based rations and 20 per cent of cereal based rations.

Unless a farmer grows soybeans expressly for livestock feeding, the only opportunity to incorporate them in rations may be when the soybeans are not suitable for the crushing industry. Frost damaged (immature) seeds have been shown to be the same in feeding value as whole soybeans when heat-treated (extruded) and feed to grower/finisher pigs.

Soybeans, like other feed ingredients, should be included in rations based on the relative cost of the nutrients they supply. Calculations of the economics of replacing soybean meal with heat-treated soybeans should include all associated costs like transportation, processing and shrinkage.

Soybeans can vary greatly in nutrient content. A chemical analysis should be conducted on the heat-treated product before mixing rations. All swine rations should be balanced for nutrients such as amino acids, minerals and vitamins, as well as energy and protein. Ration specifications should be based on expected feed intake and then adjusted to actual feed intakes.

Beyond animal performance gains, a benefit of adding fat to feed is the reduction of aerial dust. Reducing dust can improve the health status of pigs and people working in swine facilities. Cooked full fat soybeans provide the same dust control as liquid fat.

An important factor to consider when using heat processed full fat soybeans in rations is storage life. Cooked whole beans are less susceptible to rancidity than raw soybeans. But once the beans are ground for feeding, it is recommended that the meal be consumed within two weeks.

For more information contact your nearest Manitoba Agriculture and Food swine specialist.