Fatty acids profile of feedlot finished purebred Charolais and Nellore steers from advanced generations of rotational crossbreeding

The objective of this research was to evaluate the heterozygosis and genetic group effects on fatty acids profile of feedlot finished steers, straightbreds (Charolais - C and Nellore - N), and crossbreds from second (G2) (3/4C 1/4N and 3/4N 1/4C), third (G3) (5/8C 3/8N and 5/8N 3/8C) and fourth (G4) (11/16C 5/16N and 11/16N 5/16C) generation of rotational crossbreeding. The Nellore and 11/16N 5/16C meat showed higher proportion of myristic acid (C14:0) in relation to Charolais and 11/16C 5/16N meat, respectively. On the other hand, the meat of the 11/16C 5/16N steers showed higher presence of heptadecanoic acid (C17:0) and arachidonic acid (C20:4 n6) in relation to 11/16N 5/16C. The 3/4C 1/4N steers of G2 which were superior in stearic acid (C18:0) and linoleic acid (C18:2 n6c) in the total polyunsaturated fatty acids participation studied and in the ratio between polyunsaturated and saturated fatty acids, while the 3/4N 1/4C showed superiority in oleic acid (C18:1 n9c). In G3 the meat of the 5/8C 3/8N steers showed superiority in the stearic and elaidic acids (C18:1 n9t) and in the total saturated fatty acid, while the 5/8N 3/8C steers showed higher participation of the meristoleic (C14:1), cis-10-heptadecanoic(C17:1) and oleic acids and total unsaturated fatty acids. The heterosis was significant in the G2 for C17:0, C18:0, C18:1 n9c, C18:2 n6c, in the total saturated, unsaturated and polyunsaturated fatty acids. The 3/4C 1/4N steers showed the healthiest meat among the genetic groups studied, with higher presence of polyunsaturated fatty acids and higher polyunsaturated:saturated ratio.