To improve soil health in the North Central Region, a growing number of grass-fed beef producers are finishing cattle on plant-species diverse forage and/or cover crops. While beef provides many essential nutrients in the American diet, pilot data from our research team indicates that when livestock are raised and finished on plant-diverse pastures, additional health-promoting phytonutrients—terpenoids, phenols, carotenoids, and other anti-oxidants—concentrate in beef. While linkages among the plant-animal-human health continuum (“healthy plants, healthy animals, healthy humans”) are often touted as the reason why grass-fed beef may have additional health benefits, no studies have systematically assessed this.
Using novel metabolomics approaches, the goal of our work is to systematically detail the transfer of >500 biochemicals and phytochemicals from the forage/feed consumed by pasture-raised and feedlot-fed animals, to their beef, and into the body of consumers and determine metabolic health biomarkers in response to consumption.
Species composition of diets’ of cattle (grass-fed vs. grain-fed) will be characterized using DNA metabarcoding of cattle fecal samples, while phytochemical richness of forage and total mixed ration samples will be determined using metabolomics (Objective 1). Second, we will compare the presence of phytochemicals and biochemicals in both types of beef (Objective 2). To provide insight into consumer health (plasma metabolomes, inflammation, and gut microbiota communities), we will then perform a randomized controlled trial and obtain blood and stool samples from participants before and after three weeks of daily consumption of grass-fed vs grain-fed beef as part of identical diets (Objective 3). Our central hypothesis: consuming grass-fed beef results in inflammatory/metabolic signatures in the plasma and gut microbiome of indicative of improved metabolic health.
By overlaying the feed/forage metabolome (Objective 1), with the beef metabolome (Objective 2), with the consumer gut microbiome and plasma metabolome (Objective 3), our systems approach will provide an initial direct link between plant diversity, nutrient-density of beef, and human health.
Cooperating farmers will assist with sample collection, providing knowledge on grazed plants, and outreach. Findings will be shared with producers, consumers, and stakeholders in the North Central region and the US via workshops, tradeshows, articles in traditional and social media, and scientific publications. Outreach partners include the ARS-Northern Great Plains Extension program, grazing coalitions (South Dakota/North Dakota), and stakeholder groups including Understanding Ag, Thousand Hills Lifetime Grazed, Wisconsin Grass-fed beef Coop, and Carbon Cowboys. Project findings have potential for North Central grass-fed producers to improve economic viability while potentially enhancing consumer health.
Project objectives from proposal:
(a) Determine if eating grass-fed beef from cattle that ate a plant species-diverse diet elicits more healthful inflammatory and metabolite profiles in adult people than eating grain-fed beef.
(b) Translate this information back to producers and consumers by partnering with producer coalitions and stakeholder groups.
Farmers will learn how finishing cattle on biodiverse forage influences the phytochemical richness of beef.
Consumers will learn if consuming such grass-fed beef impacts their metabolic health.
Farmers can adopt biodiverse pastures and cover crops to increase healthfulness of their beef.
Consumers encouraged to seek out local grass-fed beef.