PRODUCTIVE PERFORMANCES OF MAREMMANA YOUNG BULLS REARED FOLLOWING ORGANIC RULES AND SLAUGHTERED AT 18 AND 24 MONTHS OF AGE.

Fourteen Maremmana young bulls fed on pastures supplemented with mixed hay and concentrates, according to an organic method, were slaughtered at 18 and 24 months of age to evaluate in vita and post-mortem performances. At slaughter, carcass yield was determined and carcass evaluation according to EU rules wasmade. Physico-chemical characteristics of Longissimus thoracis (LT) and Caput longum triceps brachii (TB) muscles were determined. No differences for both carcass yield and quality were found between the two age groups. Animals of 24 months of age presented lighter and more yellow meat as well as higher hue angle and drip loss. TB muscle showed lower protein content and higher shear force, moisture, total lipids and ash than LT. The latter presented a higher percentage of C15iso, whereas TB showed higher values of C18:2n6, C20:3n6, C20:4n6, C18:3n3 and C22:5n3. Maremmana animals, irrespective of age, showed a low percentage of saturated fatty acids, good PUFA/SFA ratio and a great amount of unsaturated fatty acids of the n3 and n6 series, as well as a favorable atherogenicity and thrombogenicity indexes.