Agricultural Research Service (USDA-ARS) 7 articles published in JoVE Engineering Measuring Spray Droplet Size from Agricultural Nozzles Using Laser Diffraction Bradley K. Fritz1, W. Clint Hoffmann1 1Aerial Application Technology Research Unit, USDA ARS We present protocols to be used in the measurement of spray droplet size from agricultural nozzles used in both aerial and ground based agrochemical applications. These methods presented were developed to provide consistent and repeatable droplet size data both inter- and intra-laboratory, when using laser diffraction systems. Environment The Use of High-resolution Infrared Thermography (HRIT) for the Study of Ice Nucleation and Ice Propagation in Plants Michael Wisniewski1, Gilbert Neuner2, Lawrence V. Gusta3 1U.S Department of Agriculture, Agricultural Research Service (USDA-ARS), Kearneysville, WV, 2Institute of Botany, University of Innsbruck, 3Department of Plant Science, University of Saskatechewan Here we present a protocol that allows one to visualize sites of ice formation and avenues of ice propagation in plants utilizing high resolution infrared thermography (HRIT). Biology Methods for Comparing Nutrients in Beebread Made by Africanized and European Honey Bees and the Effects on Hemolymph Protein Titers Gloria Degrandi-Hoffman1, Bruce Eckholm2, Ming Huang3 1Carl Hayden Bee Research Center, USDA-ARS, 2Coupeville, WA, USA, 3Ecotoxicology Division, Eurofins Agroscience Services, Inc. Here are methods to quantify nutrients in pollen before and after its conversion to beebread by two subspecies of honeybees. We describe techniques to measure beebread consumption and resulting protein titers in both subspecies. Biology A Hybrid DNA Extraction Method for the Qualitative and Quantitative Assessment of Bacterial Communities from Poultry Production Samples Michael J. Rothrock Jr.1, Kelli L. Hiett2, John Gamble3, Andrew C. Caudill4, Kellie M. Cicconi-Hogan1, J. Gregory Caporaso5 1Egg Safety and Quality Research Unit, USDA-Agricultural Research Service, 2Poultry Microbiological Safety and Processing Research Unit, USDA-Agricultural Research Service, 3Department of Biochemistry and Biophysics, Oregon State University, 4College of Public Health, University of Georgia, 5Department of Biological Sciences, Center for Microbial Genetics and Genomics, Northern Arizona University A novel semi-automated hybrid DNA extraction method for use with environmental poultry production samples was developed and demonstrated improvements over a common mechanical and enzymatic extraction method in terms of the quantitative and qualitative estimates of the total bacterial communities. Medicine Isolating and Using Sections of Bovine Mesenteric Artery and Vein as a Bioassay to Test for Vasoactivity in the Small Intestine James L. Klotz1, Adam J. Barnes1 1Forage-Animal Production Research Unit, USDA-Agricultural Research Service The small intestine is frequently exposed to toxins that can influence blood flow and negatively impact nutrient absorption. Using a multimyograph and mesenteric artery and vein isolates, compounds or toxins of interest can be screened for vasoactivity. Immunology and Infection Propagation of Homalodisca coagulata virus-01 via Homalodisca vitripennis Cell Culture Anna M. Biesbrock1, Christopher M. Powell1, Wayne B. Hunter2, Blake R. Bextine1 1Department of Biology, University of Texas at Tyler, 2U. S. Horticultural Research Laboratory, USDA ARS Here we present a protocol to propagate Homalodisca vitripennis cells and HoCV-1 in vitro. Medium was removed from HoCV-1 positive cultures and RNA extracted every 24 hr for 168 hr. Cell survivability was quantified by trypan blue staining. Whole virus particles were extracted post-infection. Extracted RNA was quantified by qRT-PCR. Environment A Protocol for Conducting Rainfall Simulation to Study Soil Runoff Leonard C. Kibet1, Louis S. Saporito2, Arthur L. Allen1, Eric B. May3, Peter J. A. Kleinman2, Fawzy M. Hashem1, Ray B. Bryant2 1Department of Agriculture, Food and Resource Sciences, University of Maryland Eastern Shore, 2Pasture Systems and Watershed Management Research Unit, USDA - Agricultural Research Service, 3Department of Natural Sciences, University of Maryland Eastern Shore A rainfall simulator was used to apply a consistent rate of uniform rainfall to packed soil boxes in a study of the fate and transport of urea, a nonpoint source environmental contaminant. Under uniform soil and rainfall conditions, antecedent soil moisture content exerted strong control over urea loss in surface runoff.