Influence of genetic type and level of concentrate in the finishing diet on carcass and meat quality traits in beef heifers

Abstract

Carcass and meat quality traits of thirty-six feedlot beef heifers from different genetic groups (GG) fed at two concentrate levels (CL) were evaluated using 12 - Nellore (NE), 12 - ½Angus x ½Nellore (AN) and 12 - ½Simmental x ½Nellore (SN) animals. Six heifers of each GG were randomly assigned into one of two treatments: concentrate at 0.8% or 1.2% of body weight (BW). Heifers fed concentrate at 0.8% of BW had greater (P<0.05) dressing percentage. None of the proximate analysis components of the beef were affected (P>0.05) by either CL or GG. Heifers from the AN group had higher (P<0.05) carcass weights, 12th rib fat thickness and lower dressing percentage (P<0.05) compared to the other groups. NE heifers had greater WBSF values (P<0.05) than the other genetic groups. Data suggest that the concentrate level can be reduced without compromising meat quality traits.

Quantitative genetic analysis for meat tenderness trait in Polled Nellore cattle

“…The mean WBSF value found (3.97 kg) was similar to that reported by Lage et al (2012), who obtained 3.39 kg for Nellore animals. Higher values were reported by Razook et al (2001), who, analyzing different herds of Zebu and Caracu animals, obtained values of WBSF in the Longissimus dorsi of 5.4, 4.4, 4.6 and 4.4 kg for Gir, Guzerat, Nellore and Caracu breeds, respectively.…”

“…This high variation of WBSF within a population or contemporary group has been reported previously (LAGE et al, 2012). Although there are studies indicating genetic influences on meat tenderness (SAINZ et al, 2005), this trait is highly influenced by environmental factors, ante mortem or post mortem (PARDI et al, 2005), which results in a high heterogeneity of WBSF values even within one population.…”

“…Higher values were reported by Razook et al (2001), who, analyzing different herds of Zebu and Caracu animals, obtained values of WBSF in the Longissimus dorsi of 5.4, 4.4, 4.6 and 4.4 kg for Gir, Guzerat, Nellore and Caracu breeds, respectively. Previous work shows that WBSF values tend to decrease with the addition of Bos taurus genes through crossbreeding (LAGE et al, 2012). The WBSF values also decrease as beef ageing time increases (BIANCHINI et al, 2007) and when animals are slaughtered at younger ages (BIANCHINI et al, 2007: RUBIANO et al, 2009.…”

Influence of concentrate levels in diet and body biotypes on productive variables of Guzera beef cattle

“…According to Lage et al (2012), there were no changes in meat quality variables when concentrate supplementation increased from 0.8 to 1.2% of body weight of different genetic groups: Nellore, Angus x Nellore, and Simmental x Nellore. Duarte et al (2011) reported that an increase from 40 to 80% in the concentrate promoted no alteration in cooking losses or shear force, with values of 36.8% and 5.5 kg cm -2 , respectively, which were very similar to those obtained in our study.…”

“…However, body biotype did not alter the score of the muscularity and fat of carcasses (Table 3). Increasing the concentrate from 50 to 80% could result in a greater amount of body fat provided by differences in the energetic supply related to the increase in the concentrate (ROSA et al, 2010;LAGE et al, 2012). According to Duarte et al (2011), an increase from 40 to 80% of concentrate had no effect on cold carcass weight, but increased carcass yield from 52 to 55%.…”