Low n-6/n-3 Gestation and Lactation Diets Influence Early Performance, Muscle and Adipose Polyunsaturated Fatty Acid Content and Deposition, and Relative Abundance of Proteins in Suckling Piglets

Abstract

Elevated omega-6 (n-6) and omega-3 (n-3) polyunsaturated fatty acids (PUFAs) ratios in swine diets can potentially impose a higher risk of inflammatory and metabolic diseases in swine. A low ratio between the two omega PUFAs has beneficial effects on sows' and piglets' production performance and immunity status. At present, there are few studies on how sow nutrition directly affects the protein and fat deposition in suckling piglets. Two groups of sows were fed diets with high or low n-6/n-3 polyunsaturated ratios of 13:1 (SOY) and 4:1 (LIN), respectively, during gestation and lactation. Longissimus dorsi muscle and adipose tissue from newborn piglets, nourished only with sow's milk, were subjected to fatty acid profiling by gas chromatography-mass spectrometry (GC-MS) and to proteomics assays based on nano-liquid chromatography coupled to high-resolution tandem mass spectrometry (nLC-HRMS). Fatty acid profiles on both muscle and adipose tissues resembled the magnitude of the differences between fatty acid across diets. Proteomic analysis revealed overabundance of 4 muscle and 11 adipose tissue proteins in SOY compared to LIN in both piglet tissues. The detected overabundance of haptoglobin, an acute-phase protein, and the stimulation of protein-coding genes and proteins related to the innate immune response and acute inflammatory response could be associated with the pro-inflammatory role of n-6 PUFAs.

Keywords: PUFA; adipose tissue; fat deposition; inflammation; longissimus dorsi; omega-3; omega-6; piglets; proteomics.

Figure 1

Fatty acid profile of muscle and adipose tissue samples for SOY and LIN diets. (a) Sum of saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), and polyunsaturated fatty acids (PUFAs); (b) total n-6, n-3, and the n-6/n-3 polyunsaturated fatty acid ratio; (c) major n-6 polyunsaturated fatty acid profile (linoleic acid, LA; gamma γ-linoleic acid, GLA; dihomo-gamma γ-linolenic acid, DGLA; arachidonic acid, AA); (d) major n-3 polyunsaturated fatty acid profile (alpha α-linolenic acid, ALA; eicosatrienoic acid, ETA; eicosapentaenoic acid, EPA; decosahexaenoic acid, DHA). Data are presented as LSM ± SE; significance levels: * = p < 0.05, *** = p < 0.001, **** = < 0.0001, no label = not significant, p > 0.05; n = 24 piglets for each SOY and LIN group.

Figure 1

Fatty acid profile of muscle and adipose tissue samples for SOY and LIN diets. (a) Sum of saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), and polyunsaturated fatty acids (PUFAs); (b) total n-6, n-3, and the n-6/n-3 polyunsaturated fatty acid ratio; (c) major n-6 polyunsaturated fatty acid profile (linoleic acid, LA; gamma γ-linoleic acid, GLA; dihomo-gamma γ-linolenic acid, DGLA; arachidonic acid, AA); (d) major n-3 polyunsaturated fatty acid profile (alpha α-linolenic acid, ALA; eicosatrienoic acid, ETA; eicosapentaenoic acid, EPA; decosahexaenoic acid, DHA). Data are presented as LSM ± SE; significance levels: * = p < 0.05, *** = p < 0.001, **** = < 0.0001, no label = not significant, p > 0.05; n = 24 piglets for each SOY and LIN group.