Location: Dale Bumpers Small Farms Research Center2009 Annual Report
1a. Objectives (from AD-416)
Objective 1: Determine effects of plant and endophyte genetics, management practices, and environmental conditions on sward yield, persistence, and forage quality and anti-quality factors, and the resulting animal response in forage systems in which tall fescue is a component. Subobjective 1.A. Develop a better understanding of plant physiological processes that impart persistence in tall fescue and the interaction between the plant and Neotyphodium endophyte in these processes. Use this new understanding and plant selection techniques to develop new populations of tall fescue that are either endophyte free or contain nontoxic endophytes that promote host persistence under grazing. Subobjective 1.B. Determine the potential toxicity of tall fescue grazing systems, including complementary grazing, intensive grazing, and stockpiling, by better understanding how plant physiological, morphological, and genetics factors, and pre- and post-harvest management decisions affect ergot alkaloid content. Objective 2: Determine management schemes for the sustainable production of small ruminants from temperate pastures. Objective 3: Improve inorganic and organic fertilizer use efficiency in pastures. Subobjective 3.A. Improve the efficiency of organic and inorganic fertilizer use in pastures by incorporating nutrients into the soil. Subobjective 3.B. Evaluate the effects of grazing systems and buffers on the loss of agrochemicals from pastures and hay fields.
1b. Approach (from AD-416)
Replicated field experiments will evaluate cow-calf and stocker management practices and genotypes on novel endophyte-free or -infected tall fescue pastures to alleviate fescue toxicosis and improve calf production. Grazing and management systems will be developed for sheep and goat production to manage gastrointestinal nematodes and improve post-weaning gains of lambs and kids. A tractor-drawn implement to incorporate poultry litter under the soil surface in perennial pasture will be developed, and a comparison of nutrient losses from applied poultry litter compared to conventional surface application will be examined. Cattle grazing systems and buffers will be examined to reduce the loss of agrochemicals from pastures and hay fields by collecting runoff water samples from watersheds for sediment and nutrient analyses and soil properties will be characterized. Management practices will be evaluated that optimize the proportion of a landscape/farm in temperate pastures and silvopastures to maximize environmental and economic returns. Potential bioenergy feedstocks will be examined for their suitability to integration in mid-South pasture and silvopasture systems.
3. Progress Report
In Objective 1A, soil nutrient effects on endophyte toxins have been examined and results are currently being written up. First, tall fescue was treated with either commercial fertilizer or poultry litter and plants harvested over a 3-year period for analyses of toxins from the endophyte and from surface ergot. Second, application of phosphorus and lime to tall fescue occurred to examine fescue toxins. Finally, clethodim, an herbicide, was applied at low rates to determine its effect on toxin levels in tall fescue. The results are currently being written up. In Objective 2, in an effort to improve post-weaning gains of sheep and goats and decrease internal parasites, animals grazed summer annual forages. Higher stocking rates on cowpea, soybean, and pearl millet made good use of forage, evidenced by increased weight gains during pearl millet's vegetative stage and throughout the summer for cowpea and soybean forages, but control of internal parasites was not improved by late summer unless a lighter stocking rate was used. Use of these summer annual forages may not be economical at lighter stocking rates. Black locust, a leguminous tree that contains condensed tannins, was fed to growing goats to examine changes in internal parasites. There were no changes relative to a control group, but the condensed tannins may have become inactive after high summer temperatures before harvest of the trees or leaves. In Objective 3A, testing of the prototype poultry litter incorporator has been initiated with field studies to determine its ability to minimize nutrient losses and to control odors from poultry litter applied to perennial pastures and other no-till agricultural production systems by comparing to conventional surface applications. Treatments have been applied to constructed watersheds for a runoff study in Arkansas, and samples have been collected for analyses. The prototype has been used to apply poultry litter under the surface of research plots in Arkansas, Maryland, and Pennsylvania.
1. Dried sericea lespedeza for control of gastrointestinal parasites: Gastrointestinal parasites represent a major health challenge to small ruminants, and effective alternatives to control dewormer-resistant parasites are needed for organic and conventional production. Scientists at the Dale Bumpers Small Farms Research Center, Booneville, Arkansas; Auburn University; Fort Valley State University; and Louisiana State University determined that providing 50 to 75% of dried sericea lespedeza in the diet can lead to reduced worm problems in small ruminants, potentially replacing chemical dewormers and providing nutrients for the animals. This dried plant can be used as part of an integrated control system in sheep and goat production.
2. Rotational grazing of lambs infected with gastrointestinal worms: Widespread resistance of gastrointestinal worms to chemical dewormers and the need to control these parasites without risk of chemical residue has led to the need for alternative parasite management. Rotational grazing of pastures as a means to control internal parasites has been suggested by the U.S. National Organic Program, but has never been examined without use of chemical dewormers. Scientists at USDA, ARS in Booneville, Arkansas; Louisiana State University; and Fort Valley State University determined that rotational grazing of lambs on bermudagrass led to fewer deworming treatments. Rotational grazing can be included in an integrated system of controlling internal parasites in sheep.
3. Effect of endophyte-infected tall fescue on reproductive ecology of bluebirds: Tall fescue is one of the most important pasture grasses in the southeastern US. However, it is often infected with a fungus that makes the plant more tolerant to drought and pests, but can lead to problems in animals that consume endophyte-infected tall fescue. Scientists at the University of Arkansas and USDA, ARS, Booneville, Arkansas, determined that Eastern bluebirds (Sialia sialis) laid smaller eggs, nestlings tended to be in poorer condition, and weight of nestlings at the time of first flight was lower in endophyte-infected compared with endophyte-free tall fescue pastures even though arthropod numbers were greater or there was more food. Bluebird preservation efforts should avoid endophyte-infected tall fescue pastures.
4. System for applying dry poultry litter below the pasture surface: Poultry litter provides a rich source of nutrients for perennial forages, but the current practice of spreading litter on the surface of pastures leads to significant nutrient losses of the litter that decrease nutrient-use efficiency and often lead to serious odor, air-quality, and water-quality problems. Scientists at the Dale Bumpers Small Farms Research Center (DBSFRC), Booneville, Arkansas, found that placing poultry litter applications below the pasture surface can decrease these problems by more than 90%. The DBSFRC research team has developed a prototype machine known as the ARS Poultry Litter Subsurfer in cooperation with the National Soil Dynamics Laboratory to make this technology a practical management option for producers. This technology has the potential to improve pasture productivity and help solve both air-quality and water-quality problems on millions of acres, including those associated with excessive nutrient loading into municipal water supplies.
5. Significant Activities that Support Special Target Populations
Scientists have participated in activities targeting minority, historically under-served operators/stakeholders including: 1) collaborator on a SARE grant awarded to 1890s institution Fort Valley State University, and a SARE grant awarded to this USDA, ARS station with Fort Valley State University listed as a co-principal investigator; 2) cooperator on Capacity Building Grants awarded to Fort Valley State University, Delaware State University, and Virginia State University; 3) participant in meetings of the Southern Consortium for Small Ruminant Parasite Control, attended by 1890s institute representatives from Fort Valley State University, North Carolina A&T State University, Delaware State University, and Hispanic-serving University of Puerto Rico; 4) collaborator with Virginia State University and Langston University on research projects involving small ruminant parasite control; 5) collaborator with University of Maryland Eastern Shore on implement to incorporate poultry litter into soil for fertilizer. Scientists have participated in activities targeting small farmers, including: 1) education of small ruminant extension agents and producers in the use of methods to control gastrointestinal parasites; 2) review panel for Southern Region SARE producer grants; 3) on-farm organic research in small ruminants at the Heifer Ranch of Heifer International, Perryville, Arkansas, and two private farms in Oklahoma; 4) preparation for a field day for small ruminant producers.
Moore, D., Terrill, T., Kaouakou, B., Shaik, S., Mosjidis, J., Miller, J., Vanguru, M., Kannan, G., Burke, J.M. 2008. The effects of feeding sericea lespedeza hay on growth rate of goats naturally infected with gastrointestinal nematodes. Journal of Animal Science. 86:2328-2337.