MEAT QUALITY FROM CHAROLAIS BULLS FED DIETS WITH DIFFERENT LEVELS OF CORN SILAGE INCLUSION

A sample of 6 intensive beef farms was selected according to the feeding plan adopted during the fattening period of Charolais bulls. Two farms did not include any corn silage in the diet (CS0), while corn silage represented 22% of the dietary DM in the second group of 2 farms (CS22), and it raised up to 44% of the dietary DM in the last 2 farms (CS44). Five bulls were randomly selected from each farm to be slaughtered in the same abattoir. Bulls age was similar across treatments but the CS44 bulls had a lower carcass weight (396 kg) than the other two treatments (436 and 446 kg for CS0 and CS22, respectively). Carcass fleshiness (SEUROP) and fatness scores were not affected by the level of corn silage in the diet. Meat quality was evaluated on a joint sample of the m. Longissimus thoracis, excised from the 5th to the 9th rib of each right half carcass 24 h post-mortem, after an ageing period of 10 d vacuum packaged at 4°C. Meat chemical analysis showed no variations in pH, DM, intramuscular fat and protein content due to the different silage inclusion in the diet. Only the cholesterol content was progressively reduced in the meat of bulls fed increasing quantities of corn silage according to a significant negative linear trend. Meat colour, cooking losses and shear force values were not affected by the diet. Therefore, based on these findings there are no substantial arguments against the use of a large amount of corn silage in the fattening diets of Charolais bulls