Written by: Dr. Jacquie Jacob, University of Kentucky
Sunflower is a common oilseed. Whole sunflower seeds can be included in broiler diets at levels of 15% to 20% of the diet content. Sunflower seed meal is a by-product of oil extraction from sunflower seeds. Solvent extraction is a more effective means of oil extraction than mechanical extraction. The mechanical screw-press method of oil extraction results in a high-oil sunflower seed meal. Research suggests that sunflower seed meal high in oil can constitute up to 28% to 30% of a broiler diet with no adverse effects on growth or feed efficiency. Pelleting the meal can improve feed efficiency.
Lysine is the most significant limiting amino acid in diets that use sunflower seed meal as the main protein source. Seed processing times and temperatures affect the amount of lysine available in the final meal. The fiber level of the meal depends on the extent to which the seed hulls are removed prior to oil extraction. Maintaining higher levels of hulls improves oil-extraction efficiency, but it also increases the fiber content of the meal, reducing its potential as an ingredient in poultry diets. Variability in the percentage of hulls remaining after oil extraction is the reason that different sources of sunflower seed meal produce highly variable outcomes in poultry performance.