Does distillers' grains supplementation affect beef cattle performance, carcass characteristics, and meat quality? A meta-analysis study

This study evaluated, through meta-analysis, the effect of distillers' grains (DG) supplementation to beef cattle on their performance, carcass parameters, and meat fatty acid profile. Eighty-one peer-reviewed publications with 439 treatments means were included in the data set. The effects of DG supplementation to beef cattle were evaluated using weighted mean differences (WMD) between the control group (diets with no DG) and DG group (diets with DG). Heterogeneity was explored by meta-regression and subgroup analysis using genetic type, treatment period, DG type, amount of DG in diet (g DG/kg DM), sulfur in diet (g S/kg DM), ether extract in diet (g EE/kg DM), feed systems (pasture or total mixed ration), and concentrate level in the diet (g/kg DM). Meat fatty acid profile was more affected when DG was fed to crossbreed animals. In Angus animals, DG inclusion to the diets had little effect on meat fatty acid profile whereas, a pronounced reduction was reported in meat omega-6/omega-3 ratio. In response to DG inclusion to the diets, an increase in diet sulfur content up to 6.0 g/kg and ether extract content up to 110 g/kg had no adverse effects on performance, carcass parameters, and meat physicochemical characteristics. Distillers' grains inclusions in amounts between 500 and 600 g DG/kg provided the greatest responses when evaluating carcass parameters and meat fatty acid profile. Increased CLA c9 t11, linolenic acid, and total PUFA and reduced myristic acid concentration in meat were reported when animals were fed diets containing DG.

Concentrate supplementation with dried corn gluten feed improves the fatty acid profile of longissimus thoracis muscle from steers offered grass silage

BACKGROUND

Concentrate supplementation of a grass silage-based ration is a typical practice employed for indoor winter finishing of beef cattle in many temperate countries. Plant by-products, such as dried corn gluten feed (CGF), can be used to replace conventional feedstuffs in a concentrate supplement to enhance the sustainability of ruminant production systems and to improve meat quality. This study examined the chemical composition, fatty acid profile, oxidative stability and sensory attributes of beef (longissimus thoracis muscle) from steers offered grass silage and concentrate supplements containing varying levels (0%, 25%, 50%, 75%) of CGF substituted for barley / soybean meal.

RESULTS

Feeding 50%CGF decreased the protein content and increased intramuscular fat in comparison with 25%CGF. Total phenol content and iron-reducing antioxidant power followed the order: 0%CGF > 50%CGF and 25%CGF > 0%CGF = 50%CGF, respectively. Compared to 0%CGF, 25%CGF and 75%CGF decreased C14:0 and increased C22:2n-6, C20:5n-3 and total n-3 polyunsaturated fatty acids whereas 75%CGF increased conjugated linoleic acids and C18:3n-3. Diet did not affect the oxidative stability and sensory attributes of beef patties.

CONCLUSION

The inclusion of up to 75%CGF in a supplementary concentrate for steers increased the proportion of health-promoting unsaturated fatty acids without negatively influencing the shelf-life and eating quality of longissimus thoracis muscle. © 2021 Society of Chemical Industry.