Determination of ether extract digestibility and energy content of specialty lipids with different fatty acid and free fatty acid content, and the effect of lecithin, for nursery pigs

Abstract

Various specialty lipids are commercially available and used in nursery pig diets but may have fatty acid profiles and FFA content that affect their caloric value. In each of 2 experiments, 54 barrows (28 d of age) were fed a common diet for 7 d, allotted to dietary treatments, and fed their respective experimental diets for an additional 17 d followed by a 4-d total fecal and urine collection period to determine DE, ME, and ether extract (EE) digestibility of various lipid products or lipid-lecithin combinations. In Exp. 1, 5 sources of specialty lipid products were evaluated. Small differences in DE and apparent total-tract digestibility of EE were observed among these products, with the product containing high FFA derived from animal fat having greatest DE, ME, and apparent total-tract digestibility of EE (P < 0.05). In Exp. 2, a refined soybean oil (SO) and a SO containing high FFA content (SO-FFA) were fed with or without a de-oiled soybean-based lecithin (LEC). There was an interaction between lipid source and lecithin where LEC decreased DE, DE as a percentage of GE, and ME when included with SO-FFA, but not when added to SO (P < 0.01). When no LEC was added, there was no difference in energy or EE digestibility between SO-FFA and SO. In conclusion, the specialty lipid products evaluated were poorly digested, the addition of LEC to SO or SO-FFA did not improve lipid or energy digestibility, and the presence of high FFA in SO did not negatively affect lipid or energy digestibility.