Effects of illegal treatments on meat quality of Charolaise bulls

This study investigates the effects of illegal administration of growth promoters on meat quality of Charolaise bulls. Thirty finishing Charolaise bulls (initial LW=596±21.0kg; age=479±47.7days), were randomly divided into four groups: D, E, P (n=6 animals each group) and C (n=12). The D, E and P groups were respectively administered: 0.7mg head/day/os of dexamethasone for 40 days, 20mg head/week im of 17- beta-estradiol for 5 times, 15mg head/day/os of Prednisolone for 30 days. The C group served as control. Samples of m. longissimus thoracis were taken to evaluate: pH1h, drip loss, meat color, total WHC and ring area and WHC trend, meat cooking shrinkage (MCS), MCS cooking loss, peak in Stress resistance and Relaxation (SRR) and SRR elastic coefficient. The treated groups showed a different behavior. P group had the lowest pH1h, CIE a* and b* and total WHC area values and the highest Drip Loss and MCS values. The Canonical Discriminant Analysis shows a significant separation between control and treated groups. The first canonical variable explains the 75% of between-class separation distinguishing the P group from the others, due to the total WHC area, the color parameters a* and b* and pH1. The second canonical variable explains the 16% and divides the two treated D and E groups from group C, due to the color parameters a* and b*. Meat quality is affected by growth promoter administration. The observed parameters clearly separate group D from the other groups and less clearly group E and P from control group.