Effects of supplementing growing steers with high levels of partially hydrogenated tallow on feed intake, digestibility, live weight gain, and carcass characteristics

Abstract

Effects of supplementing growing steers consuming forage-based diets with high levels of partially hydrogenated tallow on feed intake, digestibility, live weight gain, and carcass characteristics were determined in this study. In Exp. 1, Holstein steer calves were fed bermudagrass hay alone (Control) and with a ground corn-based concentrate at .95% BW (DM basis) plus partially hydrogenated tallow at 0 (Basal), .33 (low fat; LF), or .67% BW (high fat; HF) in a Latin square. Total DMI was increased by concentrate supplementation and was lower for HF than for LF (P < .05; 3.18, 3.83, 4.25, and 3.17 kg/d for Control, Basal, LF, and HF, respectively). In Exp. 2, grazing Angus x Hereford steers (270 kg +/- .4 initial shrunk BW) were fed the same supplements as in Exp. 1 for 84 or 98 d and slaughtered. Live weight gain was increased (P < .05) by concentrate supplementation (1.01, 1.34, 1.41, and 1.30 kg/d for Control, Basal, Low, and High, respectively). The concentration of total lipids in longissimus muscle was 2.51, 2.53, 3.05, and 3.03% of wet tissue for Control, Basal, LF, and HF, respectively (Basal > the mean of LF and HF; P < .07); the proportion of palmitic acid in total fatty acids was similar among treatments. Fat supplementation did not markedly affect sensory, taste, or tenderness characteristics of longissimus muscle. In conclusion, supplementing grazing beef steers with high levels of partially hydrogenated tallow, with slaughter at approximately 400-kg shrunk BW, tended to increase fat in longissimus muscle without altering the palmitic acid level in fatty acids, although sensory, taste, and tenderness characteristics were not modified.

Meat Characteristics of Nellore Cattle Fed Different Levels of Lipid-Based Diets

“…This result may be explained by the fact that ruminant diets with high concentrations of partially or completely protected fat may lead to increased levels of intramuscular fat and, in some cases, meat tenderness may be negatively affected (Patil et al, 1993), as observed in the present study.…”

“…According to Patil et al (1993), when ruminants are fed high concentrations of fat, either partially or completely protected from the microbial action of the rumen, there may be an increase in percent intramuscular fat and changes in the fatty acid profile. However, the same authors mentioned that these are small changes, which may explain the absence of difference of FA profile in the PL treatment compared with the other lipid sources.…”

Milho grão seco ou úmido com sais de cálcio de ácidos graxos para novilhos Nelore em confinamento

“…Não foram observados efeitos do tipo de grão de milho ou dos SCAG sobre a força de cisalhamento (Figura 1) ou as perdas por cocção (Figura 2). Resultados semelhantes foram relatados por Patil et al (1993), que não observaram efeito do nível de gordura na dieta sobre a força de cisalhamento ou as perdas por cocção. Aferri et al (2005) e Margarido et al (2005) também não observaram influên-cia da adição de SCAG na dieta de novilhos sobre a força de cisalhamento.…”

Milho grão seco, úmido e sais de cálcio de ácidos graxos em dietas para novilhos Nelore em confinamento: desempenho, características de carcaça e perfil de ácidos graxos

“…De acordo com Patil et al (1993), para o mercado dos EUA, um mínimo de 3% de gordura intramuscular é necessário para obtenção de uma palatabilidade aceitável. Esses valores são normalmente obtidos através do fornecimento de dietas com altas percentagens de grãos e pelo abate de animais com elevada maturidade.…”

“…Como resultado, o estearato é o primeiro ácido graxo disponível para absorção no trato digestivo (Chang et al, 1992), no entanto, o oleato é o ácido graxo predominante no músculo e tecido adiposo dos bovinos, indicando que o estearato absorvido é modificado antes da deposição no tecido dos ruminantes (Chang et al, 1992 A suplementação de bovinos a pasto com altos níveis de gordura animal parcialmente hidrogenada tendeu a aumentar a percentagem de gordura intramuscular, mas o perfil de ácidos graxos não foi negativamente influenciado (Patil et al, 1993 Os animais alimentados com dietas contendo CLA protegido apresentaram uma maior concentração total de CLA total na gordura.…”