PSXII-4 Beef quality from animals in long term feeding with DDG’s in the diet

Abstract

Dried distiller grains with solubles (DDG’s) represent an alternative to replace protein sources. The trial included 2 seasons: growing in pasture (Brachiaria brizantha, Marandu grass) for 5 months (wet), and finishing in the dry season (100 d). Two different feeding approaches were applied in the dry season: Express Feedlot® (EF) - high concentrate in pasture (1.5% of BW), or conventional feedlot (CF) - 70% concentrate. The pastures were divided into 9 paddocks totaling 9.9 ha (wet season). Sixty-nine Nellore bulls (12 mo; 249.03 ± 36.84 kg), were divided in 3 treatments: conventional supplement (CON) with cottonseed meal as a protein source; DDG’s replacing 50% of protein source (DDG50) or 100% of protein source (DDG100). In the dry season, the animals maintained the same protein source treatment (CON, DDG50 and DDG100) applied either on EF or CF. EF bulls (n = 33; 392 ± 33.18 kg BW) were finished on Marandu grass in 9 paddocks (3 by treatment). CF bulls (n = 36; 391 ± 35.2 kg BW) were confined in 9 collective pens (3 by treatment). Animals were slaughtered with the same age and the carcasses were refrigerated (0°C - 48 h). Samples were collected from the longissimus to determine pH, L* (lightness), a* (redness), b* (yellowness), CKL (cooking losses) and WBSF (Warner-Bratzler shear force). The pH, L*, a*, b* and WBSF were not influenced by finishing system (P > 0.05). However, CKL was greater (P = 0.002) in beef from animals finished in EF. The use of DDGS in long-term feeding replacing the protein sources in the diets did not influence the beef quality traits (P > 0.05). Animals in EF produces beef with the same quality from animals finished in CF. The use of DDG’s replacing protein source in long term feeding can be used without promotes negative impact on beef quality.