The effect of flaxseed supplementation on growth, carcass characteristics, fatty acid profile, retail shelf life, and sensory characteristics of beef from steers finished on grasslands of the northern Great Plains1,2

Abstract

The objective of this trial was to determine if daily supplementation of flaxseed for 85 d to steers finished on grasslands of the northern Great Plains would influence growth and carcass characteristics or the fatty acid profile, tenderness, and sensory characteristics of beef steaks. Eighteen Angus yearling steers (initial BW 399 ± 21 kg) were randomly divided into 3 groups. Steers in treatment 1 (FLX; n = 6) received a daily supplement of ground flaxseed (0.20% of BW), whereas steers in treatment 2 (CSBM; n = 6) received a daily supplement of ground corn and soybean meal (0.28% of BW), with contents of CP and TDN being similar to the supplement for FLX. Control steers (CONT; n = 6) were not supplemented. Treatments were given to each individual steer in side-by-side stalls and were fed from mid-August to November 7, 2007, the day before slaughter. All steers grazed growing forage from early May through the first week of November. Growth rate of steers fed FLX was 25% greater (P < 0.01) than that of steers fed CONT, but was similar (P = 0.45) to that of steers fed CSBM. No differences were observed for carcass characteristics (P ≥ 0.14), tenderness (Warner-Bratzler shear force; P ≥ 0.24), or sensory attributes (P ≥ 0.40) except for a slight off-flavor detected in steaks from steers fed FLX compared with CONT (7.4 vs. 7.8, respectively, with 8 indicating no off-flavor and 1 indicating extreme off-flavor; P = 0.07) and CSBM (7.9; P = 0.01). The n-3 fatty acids α-linolenic acid and eicosapentaenoic acid were 62 and 22% greater, respectively, in beef from steers fed FLX compared with those fed CONT (P < 0.001). The ratio of n-6 to n-3 fatty acids was smaller (P < 0.001) in beef from steers fed FLX compared with the ratios in beef from steers fed CONT and CSBM. Daily supplementation of flaxseed to steers grazing growing vegetation on the northern Great Plains may improve growth rate and enhance the n-3 fatty acid profile of the steaks.

Adipose tissue and muscle fatty acid profiles of steers fed red clover silage with and without flaxseed

“…In general, FA profiles differ among tissues presumably as a result of differences in their accretion of specific FA (Hood and Thornton, 1976) and desaturase and/or elongase enzyme activity (Chang et al, 1992). The levels of ALA obtained in the current study are greater than those reported earlier when beef cattle were fed either grain-based (Juá rez et al, 2011;Mach et al, 2006) or forage-based (He et al, 2012;Kronberg et al, 2011;Nassu et al, 2011) diets supplemented with flaxseed. These results could be linked to the large difference in ALA content between flaxseed and control diets (51.0% vs. 27.8%).…”

“…The proportions of RA and VA in perirenal, subcutaneous and intramuscular fat reached unprecedented levels in beef and were two to three times higher than those reported previously (He et al, 2012;Kronberg et al, 2011;Nassu et al, 2011) when feeding flaxseed in high-forage diets. The amount of RA in beef tissues of steers fed flaxseed has been reported to reflect endogenous synthesis via tissue desaturation of ruminally derived VA (Mosley et al, 2006).…”

Animal performance, carcass characteristics and beef fatty acid profile of grazing steers supplemented with corn grain and increasing amounts of flaxseed at two animal weights during finishing

“…when supplemented throughout the fattening period with 0.5% BW of corn grain or an isocaloric amount of a soybean hulls and corn oil (Pavan and Duckett, 2008), with increasing amount of corn oil (0.075% or 0.15% BW; . A trend to increase subcutaneous fat thickness was also observed in a two year study when grazing steers were supplemented with 0.75% BW of corn grain for 105 d (Wright et al, 2013); whereas no increases in subcutaneous fat were reported when steers grazing a typical grasslands from the northern Great Plains were supplemented for 85 d at finishing with only 0.20% BW flaxseed or 0.28% BW corn, soybean meal, and molasses mix (Kronberg et al, 2011). In addition, Latimori et al (2008) observed that increasing corn grain supplementation level (0%, 0.7% and 1% BW) to grazing steers throughout the fattening period reduced the period needed to reach the finishing point, suggesting an increase in subcutaneous fat accretion with supplementation.…”

Sustainability of US Organic Beef and Dairy Production Systems: Soil, Plant and Cattle Interactions

“…However, grazing-based dairy and beef systems (including certified organic systems) do not have exclusive claims to these greater levels of potentially beneficial components in meat and milk products. It is possible to increase beneficial fatty acids and other nutritional components of meat and milk in confinement feeding through the use of supplemental feeds such as oilseeds [90,91] or fish oil [92].…”