Year: 2019

Our research manuscript “A Nutritional Survey of Commercially Available Grass-Finished Beef” has been published in Meat and Muscle Biology™ , the official publication of the American Meat Science Association. 

Read the whole manuscript online or download a pdf copy.

From the abstract: Consumer interest in the source of their food, its environmental footprint, and the impact of diet on health has supported the growth of the grass-finished beef (GFB) industry. Studies have concluded that GFB has distinct nutritional differences from conventionally-finished beef. As the GFB industry continues to expand, it is vital to continue to explore the nutritional complexities and variation in the product. To achieve this, a survey of grass-finishing production systems throughout the USA was conducted, and beef finished on the participating farms was analyzed for its nutritional composition, including fatty acid (FA), mineral and fat-soluble vitamin contents. Samples were analyzed from 12 producers and annual production capacity of farms ranged from 25 to 5,000 cattle, with a mean age of cattle at harvest of 26.8 ± 2.30 mo. An array of finishing diets included grazing exclusively in perennial pasture, incorporating annual forage crops, and feeding a variety of harvested forages with supplementation of non-starch feed byproducts. Beef muscle tissue FA content was analyzed by gas chromatography-mass spectrometry (GC–MS). The mean ratio of omega-6 (n-6) to omega-3 (n-3) FA in samples varied significantly by producer, ranging from 1.80 to 28.3 (P < 0.0001), with an overall sample set median of 4.10. A selection of minerals including iron, magnesium, and potassium were analyzed by ICP emission spectroscopy and mineral content significantly differed by producer for all minerals (P < 0.001). Mean α-tocopherol and β-carotene content was 610.6 µg/100 g beef and 32.2 µg/100 g, respectively. The amount of these antioxidants also varied between producers (P < 0.0001), but tended to be greater in beef finished solely on fresh forages. This survey indicates that commercially available GFB can vary in nutritional composition due to the diverse practices used to grass-finish cattle.

In 2017, the research team identified the “honeysuckle” woods on the property where the honeysuckle removal project will happen.  Three main treatments (basal spray, hand cut stems and mechanical removal) will be applied to different areas of the woods and the impact on vegetation and seedlings monitored.  A separate property in Indian Hill will remain untreated and serve as the control for the experiment. The main treatments will then be subdivided into additional treatments. In the basal spray treatment the honeysuckle skeletons will be left standing in some locations or removed the following spring.  There is some evidence that standing dead honeysuckle protects emerging tree seedling from deer browsing. The hand cut stems will either have herbicide applied to the stumps or this application will be delayed until fall when a foliar spray will be applied. Finally the mechanical cutting of the honeysuckle will be followed by spraying while other areas will see a delay and foliar spray applied in the fall.  Subsequent monitoring will help us determine which treatment is most effective at producing a thriving community of tree seedlings and native vegetation.

Image A shows hand cut stems sprayed with herbicide and image B shows the result of large scale mechanical removal of honeysuckle.  The research team is collecting data on what happens next after different honeysuckle removal strategies are employed.

We have just completed our first year of monitoring and established some baseline data.  In the understory, invasive shrubs and vines are growing throughout our woodlands. In areas of higher native diversity, the dominance of invasive species is lower.  In understories thick with honeysuckle there are very few seedlings and saplings. Our canopy data show a rise of red maples is happening across the property. Red maples have physiological properties that make them successful in both early and late successional stages of the forest.  Based our surveys, our oak hickory forest is being replaced by other hardwood species such as maple and beech. The large oaks and hickories close the canopy for light, and oak and hickory seedlings are not shade tolerant compared to the other species found in the woods. We will keep documenting this shift.

This diagram represents data from one of our most diverse communities (oak hickory).  Twenty six species were observed over the summer and fall seasons and the most frequent species (seen in 4/5 or 5/5 plots) are pictured.   The three invasive species observed in high frequency were chickweed, honeysuckle and winter creeper.