The Influence of Heat Treatment and Solvent Upon the Nutritive Value of Soybean Oil Meal for Swine

Abstract

The influence of heat treatment and solvent used in the processing of soybeans upon the nutritive value of the meal produced was tested with the growing-fattening pig. Soybean residues which had been, (A) hexane extracted-desolventized,(B) hexane extracted-partially toasted, (C) hexane extracted-regularly toasted, and (D) trichloroethylene extracted-regularly toasted were studied. Each meal was fed as a supplementary source of crude protein with yellow corn, alfalfa meal, and minerals to pigs on winter rye pasture from weaning to 200 pounds. All rations were fed with and without aureomycin HCl at 5 mg. per pound. During early growth results showed that B, C, and D did not differ significantly but they were superior to A; whereas, for the entire study differences widened so that B was also superior to D which, in turn, failed to statistically excel A. Apparently D possessed no toxic properties. Aureomycin stimulated a significant increase in gains from weaning to 100 pounds;whereas, its effect to final weight was not statistically significant. The magnitude of the response to aureomycin varied directly with the length of heat treatment applied to the soybean residue; supplementary aureomycin with ration containing A failed to produce a growth response.Pigs yielding a growth response to the antibiotic exhibited a thicker backfat than controls. In a protein efficiency test, semi-purified rations containing 10 percent crude protein solely from the test soybean oil meals were fed to weanling pigs in drylot for 37 days. The results indicated all of the meals tested were significantly different in protein quality. Copyright © . .