Lipid Sources in Poultry Diets: Metabolic Effects, Physiological Implications, and Modulation of Egg Yolk Fatty Acid Composition

Lipids play a central role in poultry nutrition by modulating energy utilization, nutrient digestibility, and metabolic processes related to lipid absorption and deposition. This review synthesizes current knowledge on the main dietary lipid sources used in poultry nutrition and their effects on performance, lipid metabolism, and egg yolk fatty acid composition. Conventional lipid sources, including vegetable oils and animal fats, differ in fatty acid profile, degree of saturation, and digestibility, which directly influence metabolic efficiency and productive responses. In addition, the strategic use of lipid sources enables the modulation of fatty acid profiles in poultry products, particularly through the enrichment of polyunsaturated fatty acids such as omega-3. These effects are associated with mechanisms involving lipid digestion, absorption, and hepatic lipoprotein synthesis, which regulate fatty acid deposition in tissues and egg yolks. However, responses to dietary lipids are influenced by factors such as inclusion level, oxidative stability, and lipid composition. Overall, dietary lipid manipulation represents an effective strategy to optimize production efficiency and enhance the nutritional quality of poultry-derived foods.