Sunflower meal, which is the co-product derived from sunflower seeds after oil extraction, has a high concentration of digestible amino acids (AA) and fiber. The nutritive value and quality of sunflower meal is partially dependent on the degree of dehulling, the variety of the sunflower, and the oil extraction process. Sunflower seeds are initially de-hulled and then partially de-oiled using a mechanial prepress procedure. A second de-oiling procedure is performed using a solvent extraction procedure or by usign a second mechanical expelling procedure. The prepress-solvent extraction procedure results in production of sunflower oil and sunflower meal that contains 1 to 3% oil, whereas the double-press procedure results in production of sunflower oil and a sunflower product that contains 5 to 10% residual oil and commonly is referred to as sunflower expellers. Some of the hulls may be added back to the sunflower meal or the sunflower expellers resulting in differences in concentrations of total dietary fiber among sources.

The apparent ileal digestibility and the standardized ileal digestibility (SID) of crude protein (CP) and AA in individual sources of partially de-hulled sunflower meal fed to pigs have been reported. However, there are no comparative values for the SID of AA in sunflower meal produced in different parts of the world, and it is not known if the SID of AA in sunflower meal are different from those in sunflower expellers. Therefore, the objective of the current study was to test the hypothesis that there is no difference in the SID of CP and AA in different sources of sunflower meal and sunflower expellers obtained from different countries.