The aim of this study was to evaluate the viability of the use of spent laying hens' meat in the manufacturing of mortadella-type sausages with healthy appeal by using vegetable oil instead of animal fat. 120 Hy-line ® layer hens were distributed in a completely randomized design into two treatments of six replicates with ten birds each. The treatments were birds from light Hy-line ® W36 and semi-heavy Hy-line ® Brown lines. Cold carcass, wing, breast and leg fillets yields were determined. Dry matter, protein, and lipid contents were determined in breast and leg fillets. The breast and legg fillets of three replicates per treatment were used to manufacture mortadella. After processing, sausages were evaluated for proximal composition, objective color, microbiological parameters, fatty acid profile and sensory acceptance. The meat of light and semi-heavy spent hens presented good yield and composition, allowing it to be used as raw material for the manufacture of processed products. Mortadellas were safe from microbiological point of view, and those made with semi-heavy hens fillets were redder and better accepted by consumers. Values for all sensory attributes were evaluated over score 5 (neither liked nor disliked). Both products presented high polyunsaturated fatty acid contents and good polyunsaturated to saturated fatty acid ratio. The excellent potential for the use of meat from spent layer hens of both varieties in the manufacturing of healthier mortadella-type sausage was demonstrated. INTRODUCTIONAccording to statistics from the Brazilian Poultry Association (UBA, 2009), 60 million laying hens were housed in Brazil (white and brown eggs) in 2008. Considering that the number of birds housed corresponds to the amount of pullets introduced to replace old spent hens, then a similar number must have been culled in the same period. If the volume of biological matter, labor, and associated transportation costs are taken into account, the disposal of layer hens is one of the main economical and environmental problems of the poultry industry (Lyons, 2001). In addition, with the increase of broiler production, the sale of spent breeding hens at reasonable prices has become more difficult, affecting producers' profits (Kondaiah, 1993).Spent hens are usually slaughtered and used in feed production and concentrated stock preparations, or sold domestic consumption in soups and stews (Ajuyah et al., 1992; Voller-Reasonover et al., 1997). However, a better use of hens at the end of laying cycle, for example, in the manufacturing of food products with higher added value, could provide economic benefits for the Brazilian poultry industry.Brazil is a developing country and a significant part of its population has limited access to fresh beef, and is only able to buy processed meat. Therefore, the consumption of sausages is high. Mortadella is one of the most consumed sausages in Brazil, and its consumption has increased approximately 10% per year (Barbosa et al., 2006). Thus, it might be interesting to use meat of...