BACKFAT FATTY ACID PROFILE AFTER GROWING PERIOD IN IBERIAN PIGS FED WITH OLIVE CAKE IN A DRY OR WET (SILAGE) FORM

The traditional production system of Iberian pig is characterized for having a finishing period called montanera, which is based on acorn intake. This kind of handling has an influence on both product quality and animal welfare issues. Acorn based diet during montanera has a positive effect on meat quality since increases the oleic content. However, montanera has an uneven effect on animal welfare, on one hand it is a semi-extensive system which is positive but, on the other hand, a restricted diet is required during pre-montanera period to prevent a non-desirable fatness percentage in final pig products. This restriction diet implies feeding stress. The use of olive by-products during the growing phase diet of Iberian pigs could be the solution to avoid this stress. Here, we studied the effect of three different dietary regimens given to Iberian pigs in growing period (42 kg to 95 kg) on backfat fatty acid composition. A control standard diet group (CD) was compared with two diets based on olive by-products, one incorporating dry olive pulp in the feed (DD), and the other one incorporating olive cake in wet form (WD). This last one consisted of olive cake in a silage presentation offered ad libitum and supplemented with a specific feed given once a day in a restricted regimen as the CD and DD diets. A significantly higher oleic acid values was observed for DD and WD diets compared with CD diet. Therefore, the diets based on olive cake seem to be an alternative to more expensive diets based on high-oleic raw material. However, before implementation in feeds used for the growing period, further studies analyzing their effects on meat quality and production costs should be carried out.