Effects of supplemental fat on growth performance and quality of beef from steers fed barley-potato product finishing diets: I. Feedlot performance, carcass traits, appearance, water binding, retail storage, and palatability attributes1

Abstract

To measure the effects of dietary fat on feedlot performance, carcass characteristics, and beef appearance, moisture binding, shelf life, and palatability, 168 crossbred beef steers (317 +/- 1.0 kg) were allotted randomly, within weight blocks, to a randomized complete block design with a 3 x2 + 1 factorial arrangement of dietary treatments. Main effects were level of yellow restaurant grease (RG; 0, 3, or 6%) and level of alfalfa hay (AH; 3.5 or 7%), with the added treatment of 6% tallow and 7% AH in barley-based diets containing 15% potato by-product and 7% supplement fed for 165 d (all dietary levels on a DM basis). Dietary treatment did not (P >0.10) affect DMI, LM area, beef brightness, or beef texture. Level of RG linearly increased (P <0.05) ADG from 1.48 to 1.60 kg/d, diet NE(m) from 2.4 to 2.6 Mcal/kg, diet NE(g) from 1.7 to 1.9 Mcal/kg, and internal fat from 2.1 to 2.4%. Level of RG linearly increased (P <0.05) G:F from 0.184 to 0.202, but decreased (P <0.05) beef firmness score from 3.0 to 2.8 and fat luster score from 3.1 to 2.8. Level of AH did not (P >0.10) affect any of the measurements; however, AH interacted with level of RG on fat thickness and yield grade (linear; P <0.05), as well as marbling score and percentage of carcasses grading USDA Choice (quadratic; P <0.05). Fat thickness and yield grade increased with increasing RG level in 3.5%, but not in 7%, AH diets. In steers fed 3.5% RG, marbling scores and percentage of carcasses grading Choice were greatest when fed with 3.5% AH, and least when fed 7% AH. Steers fed tallow had lower marbling scores (P = 0.01) and percentage of carcasses grading Choice (P = 0.066) than those fed RG. Retail storage attributes, including visual and instrumental color, decreased during storage (P <0.01), but were not (P >0.10) affected by diet. Trained sensory panel scores for initial tenderness increased quadratically (P = 0.07) as dietary RG increased, but diet did not (P >0.10) affect drip loss, cooking loss, or trained sensory panel scores for sustained tenderness, initial and sustained juiciness, and beef flavor. Therefore, RG increased diet energy, improved performance, and increased carcass fatness; however, dietary fat and AH did not affect most measurements of water retention, color stability, or palatability of beef.

Effects of high-oil corn on feedlot performance, carcass characteristics, fatty acid profiles, beef palatability, and retail case life traits of beef top loin steaks1

“…In the present experiment, diets were formulated to contain similar concentrations of fat; nonetheless, as noted previously, the fat content of the 90% concentrate diet was slightly greater for NMR than HOC. It seems highly unlikely, however, that this small difference in dietary fat concentration would have affected marbling score, as previous studies with much greater differences in fat concentration among diets have shown limited effects on marbling score (Zinn et al, 2000;Nelson et al, 2004). Consistent with our findings, Andrae et al (2001) did not observe differences in other carcass measurements.…”

Performance and methane emissions of Nellore steers grazing tropical pasture supplemented with lipid sources

“…Lipid inclusion in ruminant diets increases the energy density and can result in better performance (Nelson et al, 2004;Rosa et al, 2013). However, fatty acids can reduce ruminal fermentability and potentially affect the performance of the animal.…”

Utilization and application of wet potato processing coproducts for finishing cattle1

“…Using the Garrett (1980) equation, peels and French fries contained 1.2 and 1.8 Mcal of NE g /kg, respectively, which are less than animal performance indicated. Due to lack of data, the energy content of the fried coproduct can be estimated as the weighted average of yellow grease in barley-or corn-based finishing diets (Nelson et al, 2004b(Nelson et al, , 2008 and hopper box coproduct (Nelson et al, 2000). These data show the impact of type of potato coproduct and cooking on energy value relative to modern, greater energy (ME, NE) containing barley varieties (Ovenell-Roy et al, 1998a,b,c).…”