Non-invasive metabolomics biomarkers of production efficiency and beef carcass quality traits

The inter-cattle growth variations stem from the interaction of many metabolic processes making animal selection difficult. We hypothesized that growth could be predicted using metabolomics. Urinary biomarkers of cattle feed efficiency were explored using mass spectrometry-based untargeted and targeted metabolomics. Feed intake and weight-gain was measured in steers (n = 75) on forage-based growing rations (stage-1, 84 days) followed by high-concentrate finishing rations (stage-2, 84 days). Urine from days 0, 21, 42, 63, and 83 in each stage were analyzed from steers with the greater (n = 14) and least (n = 14) average-daily-gain (ADG) and comparable dry-matter-intake (DMI; within 0.32 SD of the mean). Steers were slaughtered after stage-2. Adjusted fat-thickness and carcass-yield-grade increased in greater-ADG-cattle selected in stage-1, but carcass traits did not differ between ADG-selected in stage-2. Overall 85 untargeted metabolites segregated greater- and least-ADG animals, with overlap across diets (both stages) and breed type, despite sampling time effects. Total 18-bile acids (BAs) and 5-steroids were quantified and associated with performance and carcass quality across ADG-classification depending on the stage. Stepwise logistic regression of urinary BA and steroids had > 90% accuracy identifying efficient-ADG-steers. Urine metabolomics provides new insight into the physiological mechanisms and potential biomarkers for feed efficiency.

Grass-fed vs. grain-fed beef systems: performance, economic, and environmental trade-offs

Between increasing public concerns over climate change and heightened interest of niche market beef on social media, the demand for grass-fed beef has increased considerably. However, the demand increase for grass-fed beef has raised many producers' and consumers' concerns regarding product quality, economic viability, and environmental impacts that have thus far gone unanswered. Therefore, using a holistic approach, we investigated the performance, carcass quality, financial outcomes, and environmental impacts of four grass-fed and grain-fed beef systems currently being performed by ranchers in California. The treatments included: 1) steers stocked on pasture and feedyard finished for 128 days (CON); 2) steers grass-fed for 20 months (GF20); 3) steers grass-fed for 20 months with a 45-day grain finish (GR45); and 4) steers grass-fed for 25 months (GF25). The data were analyzed using a mixed model procedure in R with differences between treatments determined by Tukey HSD. Using carcass and performance data from these systems, a weaning-to-harvest life cycle assessment (LCA) was developed in the Scalable, Process-based, Agronomically Responsive Cropping Systems model framework, to determine global warming potential (GWP), consumable water use, energy, smog, and land occupation footprints. Final body weight varied significantly between treatments (P <0.001) with the CON cattle finishing at 632 kg, followed by GF25 at 570 kg, GR45 at 551 kg, and GF20 478 kg. Dressing percentage (DP) differed significantly between all treatments (P < 0.001). The DP was 61.8% for CON followed by GR45 at 57.5%, GF25 at 53.4%, and GF20 had the lowest DP of 50.3%. Marbling scores were significantly greater for CON compared to all other treatments (P < 0.001) with CON marbling score averaging 421 (low-choice ≥ 400). Breakeven costs with harvesting and marketing for the CON, GF20, GR45, and GF25 were $6.01, $8.98, $8.02, and $8.33 per kg hot carcass weight (HCW), respectively. The GWP for the CON, GF20, GR45, and GF25 were 4.79, 6.74, 6.65 and 8.31 CO2e/kg HCW, respectively. Water consumptive use for CON, GF20, GR45, and GF25 were 933, 465, 678 and 1250 L /kg HCW, respectively. Energy use for CON, GF20, GR45, and GF25 were 18.7, 7.65, 13.8 and 8.85 MJ /kg HCW, respectively. Our results indicated that grass-fed beef systems differ in both animal performance and carcass quality resulting in environmental and economic sustainability tradeoffs with no system having absolute superiority.

Improving the Quality of Broiler Duck Carcasses with the Addition of Meniran Plan (Phylanthus niruri L.) Extract as a Feed Additive

The purpose of this research was to determine the improvement of the carcass quality of broiler ducks with the addition of meniran extract as a feed additive. This is based on the fluctuating price of feed 70 – 80% is part of the operational costs and the prohibition on the use of antibiotics requires alternative feed additives that are safe for human consumption. This research was carried out in Juni – August 2021 in Dayu Village, Nglegok District Blitar Regency. The method used is experimental with 4 treatments and 3 replications. The design used is Completely Randomized Design. The result showed that giving meniran extract as a feed additive could improve the carcass quality of broiler duck including carcass weight and carcass percentage and dit not have a significant effect on slaughter weight. It is recommended to use meniran plan extract level 3% to improve the carcass quality of broiler ducks.

Certified Beef Programs: What's in a Name?

This publication discusses certified beef programs and carcass quality specifications. Written by Tracy Scheffler, Jason Scheffler, and Chad Carr, and published by the UF/IFAS Department of Animal Sciences, October 2021.