PSIII-15 - Effect of dietary fatty acids composition on growth performance, fecal consistency, and plasma fatty acid profile of weaned pigs

Abstract: Dietary lipids are an important source of energy and fatty acids (FA), which play critical roles in mucosal immune responses, epithelial barrier functions, and overall intestinal development. Therefore, including fat in nursery pig diets can be used as a nutritional strategy to optimize pig growth performance and intestinal health after weaning. This study evaluated the effects of two different dietary fatty acid compositions derived from conventional soybean oil (CSO) and/or high oleic soybean oil (HOSO) supplementation on growth performance, fecal consistency, and plasma FA profile of weaned pigs. A total of 208 weaned pigs (4.96 ± 0.8 kg) were used in a randomized complete block design and allotted to 16 pens of 13 pigs each. Experimental diets met NRC (2012) requirements and were provided in a 3-phase nursery feeding program: Phase 1 (d0-d7), Phase 2 (d8-d21), and Phase 3 (d22-d42). Pens were assigned to one of two dietary treatments consisting of two dietary FA compositions derived from the supplementation of 3% of either CSO (20% Oleic acid; 50% Linoleic acid; 6% Linolenic acid) or HOSO (44% Oleic acid; 30% Linoleic acid; 3% Linolenic acid). Feed disappearance and body weight were measured at d0, 21, and 42. Pen fecal score was assigned daily from d0 to 21 and then 3 times per week until d42. Blood samples were collected on d21 (2 pigs/pen) for plasma FA profile analysis. Performance data were analyzed using T-TEST and fecal score using PROC FREQ procedures of SAS. From d0 to 21, pigs fed CSO supplemented diets had a greater (P ≤ 0.05) body weight (8.6 vs. 7.4 kg) and daily gain (0.17 vs. 0.12 kg). In addition, daily feed intake and feed efficiency tended to be 23% and 16% greater in CSO-fed pigs, respectively. From d21 to d42, there were no differences between dietary treatments for growth performance. Overall nursery period, pigs fed CSO had greater (P ≤ 0.1) daily gain than HOSO pigs (0.34 vs. 0.30 kg). Pigs fed CSO had a greater (P ≤ 0.05) plasma concentration of palmitic, linoleic, and linolenic FA while pigs fed HOSO had a greater (P ≤ 0.05) plasma concentration of palmitoleic and oleic FA. There were no differences in fecal scores in weeks 1 and 2. However, pigs fed CSO had less incidence of soft and watery feces (χ2 < 0.1) in weeks 3 to 6. In conclusion, a greater dietary content of linoleic and linolenic FA promoted pig growth performance and reduced incidence of diarrhea after weaning compared to greater content of oleic FA.