Feeding of extruded flaxseed (linum usitatissimum L.) and pasture in podolica young bulls: Effects on growth traits, meat quality and fatty acid composition

The present trial aimed to evaluate the effect of feeding extruded flaxseed (Linum usitatissimum L.) in concentrate feed and pasture on Podolica young bulls performance and meat characteristics. Eighteen male bulls were randomly divided in three homogeneous groups and fed for 180 days two isocaloric and isonitrogenous concentrates as: (1) diet containing 350 g/kg DM of extruded flaxseed (EFS); (2) diet containing 350 g/kg DM of extruded flaxseed for the first 90 days, then bulls had also 10 h/days grazing on a natural pasture (EFSP); and (3) a control diet containing 600 g/kg of dry matter (DM) of soybean (SB) seeds. Results from growth trial of bulls showed that none of the parameters studied were influenced by the dietary treatments. In slaughter trial, feeding to extruded flaxseed and pasture had a positive effect on the meat lipid component leading to lower perirenal fat accumulation and to higher conjugated linoleic acids (CLA), arachidonic acid, polyunsaturated fatty acids (PUFA) and n-3 fatty acids contents. Additionally, in both groups fed extruded flaxseed (EFS and EFSP) the carcass fat, meat L* (lightness) values as well as meat n-3 and n-6/n-3 ratio were similar, resulting however improved compared to SB-control group. Moreover, the higher vitamin E content in extruded flaxseed-diet with pasture reduced meat lipid oxidation during storage. Our findings indicate that extruded flaxseed in concentrate can be advantageously used in grazing Podolica bulls, maintaining the growth performance and improving meat lipid profile.