EFFECTS OF PASTURE GRAZING VS FEEDLOT FEEDING ON MEAT QUALITY OF YOUNG STEERS

M. IRURUETA; ANIBAL PORDOMINGO; GRIGIONI G; CARDUZA F; ADRIANA PORDOMINGO; VOLPI LAGRECA G

China

Congreso; 53th ICoMST – International Congress of Meat Science and Technology,; 2007

For years, Argentina has been defined as a grass-fed beef producer country. Rearing and fattening cattle on grass and in their natural habitat is well appreciated by premium markets. Product and environment health attributes are often related to animal husbandry on pastures. It has also shown to be relevant from the animal welfare concern. On the other hand, other markets demand carcass weights difficult to reach by pasture finished argentine cattle. Additional concerns for some markets include fat colour, tenderness consistency and shelf life. Numerous diets have been extensively studied over the years trying to determine diet impact on beef quality attributes, relating to consumer appreciations with variable conclusions. In most cases, performance on pasture has differed notoriously from performance on full-feed in pens. Little work has been conducted on comparisons when individual performance on grass has been maintained high. Objectives of this study were to characterize performance, carcass colour attributes and sensory characteristics of young Angus steers grown and finished on pasture, compared to high and medium grain feedlot diets. Animals from T2 treatment showed greater (P< 0.05) average daily gain (ADG). Gain on pasture denoted high performance on grass. Differences between treatments were observed (P<0.05) in colour parameters. L* values were higher in T1 and T3 while a* and b* were lower (P< 0.05) for these treatments compared with T2. Fat thickness and marbling were slightly different (P<0.05). Previous research (Bennet el al., 1995; Camfield et al., 1999) has reported similar findings. These studies have also reported that marbling could be lower in grass finished cattle compared with grain finished. No significant differences in other parameters were detected. In agreement with studies of French, O’Riordan, Caffrey, Mooney et al. (2000, 2001), this study found no differences (P> 0.10) in WBSF and muscle depth or width. Results from this study showed that meat from young steers grazed on small-grain winter annual or pen-fed in confinement would differ in colour, fat thickness and marbling. Full-feeding in confinement resulted in carcasses with slightly more fat cover compared with steers finished on forage only. Evidence from this study implies, however, that no differences in muscle development and tenderness should be expected if performance on pasture is similar to the level reported here.