To the Blue Ridge

FROM COW PATTIES TO HORSE APPLES

Virginia Tech studies the ins and outs of pasture grazing at research farm in Middleburg

From cow nutrition to diapered horses, Virginia Tech has quietly been conducting agricultural experiments in Middleburg for almost 75 years. Surrounded by some of the highest priced real estate in the area, the Middleburg Agricultural Research and Extension Center lies one mile south of the quaint town of Middleburg. It’s one of 13 agricultural research farms maintained by the cooperative extension program throughout the state.

In 1949, the late local landowner and philantropist. Paul Mellon of Upperville, VA, made a gift of 420 acres of farmland to the Virginia Polytechnic Institute and State University along with financial support to help establish the Virginia Forage Research Station. Mr. Mellon envisioned forage systems that would promote animal productivity and, at the same time, maintain the integrity and fertility of the soils and the livestock they supported. Research activities began in July 1949. For the first 40 years, research at the Virginia Forage Research Station focused on cattle nutrition derived from grazing Virginia pastures.

Part of the charter of Virginia’s land grant universities Virginia Tech and Virginia State University tasks them with educating Virginians and helping them improve their lives by providing research based educational resources through a network of campuses, research farms and educators at county offices. Virginia Cooperative Extension is a product of cooperation among local, state, and federal governments in partnership with tens of thousands of citizens.

Throughout the first 40 years of the Virginia Forage Research Station, the number of cattle farms decreased while the number of horses and horse farms in Northern Virginia steadily increased. Mellon, a horseman as well as philanthropist, began discussions with a panel of distinguished scientists about areas of future study. Horse nutrition was a natural for the hunt country farm, so Virginia Tech agreed in 1986 to convert the cattle farm to begin studies of pasture based equine nutrition. Mr. Mellon endowed a professorship to lead the research and donated funds for new buildings. By October 1988, fescue pastures developed for the cattle were converted to bluegrass and clover, which is more appropriate for horses. An appeal through the Virginia Thoroughbred Association in 1990 was rewarded with the donation of 45 mares and three stallions as initial study subjects.

A nutritional survey was conducted on horses and pastures in central and northcentral Virginia to determine initial research focus. The MARE Center found pastures in this region deficient in several key minerals: copper, zinc and selenium throughout the year and phosphorus and vitamin A in the winter. This led to new findings on feeding supplements and a study of vitamin A depletion and supplementation in 1991.

A new research and conference building, with a dependent stable, was dedicated by Mr. Mellon in 1992. A name change in 1993 deemed all of Virginia Tech’s “Agricultural Experiment Stations” as “Agricultural Research and Extension Centers.” Hence, the Middleburg Agricultural Research and Extension Center gained a new acronym, “The MARE Center,” which seemed fitting.

Numerous surveys of horses, as well as research at the MARE Center on foals born there, indicate that the first year and a half of growth is not continuous, but is affected by seasonal changes. Detailed records of conditions that are less amenable to management are kept to examine what effect these may be having on growth. Examples of some of these conditions include day length, temperature, and pasture nutrient composition. Seasonal fluctuations in these factors are important modulators of growth.

Growth is closely monitored at the MARE Center with detailed records kept of the foals, weanlings and yearlings. Years of records provide researchers with a robust database of growth characteristics that are helping scientists and horse owners understand how changes in the environment that the foals are raised in may affect growth and development

One of the studies conducted at the MARE Center developed marker methods to determine pasture intake in mature horses. A marker is an indigestible substance that is fed to the horse in known amounts. By knowing the amount of marker fed to the horse, the total amount of manure produced per day, and the concentration of the marker in the manure, pasture intake could be monitored.

Horses used in these studies wore “nappies,” horse-sized diapers, which were emptied four times a day to obtain total manure production. Though they presented an odd sight, the horses could walk, trot, canter and roll without displacing the nappies. They did not appear any more inconvenienced than if they were wearing a horse blanket. Research from the diaper product helped dispel an old rule of thumb previously published in textbooks; that a horse eats approximately 2% of its body weight daily, more or less, depending on life stage and performance demands. The MARE Center horses obviously did not read the textbooks: they ate a whopping 3.3% of their body weight in pasture dry matter per day.

That translates to 33 pounds of pasture dry matter for a 1000 pound horse. Since pasture is only 25-30% dry matter (and 70-75% water), the horses actually consumed approximately 100 pounds of fresh pasture per day!

It is no wonder that pasture management is so important, both for the health of the horses and optimal use of land, a diminishing resource in this rapidly developing area and the MARE Center is continuing studies with broodmares and growing horses. Additionally, the marker methods are used to estimate fecal and urine outputs, and the loads of nitrogen and phosphorus placed on the soils and streams. The mission of the Middleburg Agricultural Research and Extension Center is to develop an ideal pasture system in which superior care and nutrition of horses not only ensures their buoyant health and promotes their performance but also protects and enhances the land. The mission is accomplished through research, graduate training and outreach activities.