Department of Veterinary and Biomedical Sciences: 2000 Annual Report

Foreword, 2000 John A . Schmitz. Professor and Department Head Veterinary and Biomedical Sciences Personnel Faculty Profiles Teaching program Research program Extension Program Nebraska Veterinary and Diagnostic Laboratory Systems Grants and Contracts Funded or Active in 2000 Patents by VBMS Faculty in 2000 Publications by VBMS Faculty in 2000 Presentations by VBMS Faculty in 2000 Articles Regarding the Department in 2000 Selected Committees, Editorial and Other Appointments of VBMS Faculty Departmental Budget Summaries Nebraska Agricultural Statistics 1999

Department of Veterinary and Biomedical Sciences 2004 Annual Report

Veterinary and Biomedical Sciences Personnel VBMS Teaching Program VBMS Research Program International Activities, 2004 Veterinary Extension Program. 2004 VBMS Grants and Contracts Program. 2004 Refereed Publications by VBMS Faculty in 2004 Department of Veterinary and Biomedical Sciences. Selected Committees, Editorial and Other Appointments. 2004 Articles Regarding the Department in 2004 Departmental Budget Summaries. 2004 Nebraska Agricultural Statistics. 2003/2004

Sapro-Zoonotic Risks Posed by Wild Birds in Agricultural Landscapes

There are over 1400 catalogued human pathogens, with approximately 62% classified as zoonotic (Taylor et al., 2001). Most evidence of direct transmission of pathogens to humans involves domestic and companion animals, whereas the reservoir for most zoonoses is wildlife; yet there are relatively few well-documented cases for the direct involvement of transmission from wildlife to humans (Kruse et al., 2004). In part, this absence of evidence reflects the mobility of wildlife, the difficulty accessing relevant samples, and the smaller number of studies focused on characterizing wildlife pathogens relative to the human and veterinary literature (McDiarmid, 1969; Davis et al., 1971; Hubalek, 2004).

Temporal and Spatial Variations of Ions, Isotopes and Agricultural Contaminants in Surface Waters and Groundwater of Nebraska's Rainwater Basin Wetland Region

The wetlands of south-central Nebraska’s Rainwater Basin region are considered of international importance as a habitat for millions of migratory birds, but are being endangered by agricultural practices. The Rainwater Basin extends across 17 counties and covers 4,000 square miles. The purpose of this study was to assemble baseline chemical data for several representative wetlands across the Rainwater Basin region, and determine the use of these chemical data for investigating groundwater recharge. Eight representative wetlands were chosen across the Rainwater Basin to monitor surface and groundwater chemistry. At each site, a shallow well and deep well were installed and sampled once in the summer of 2009 and again in the spring of 2010. Wetland surface water was sampled monthly from April, 2009 to May, 2010. Waters were analyzed for major ions, nutrients, pesticides and oxygen-18 and deuterium isotopes at the University of Nebraska Water Sciences Laboratory. Geochemical analysis of surface waters presents a range of temporal and spatial variations. Wetlands had variable water volumes, isotopic compositions, ion chemistries and agricultural contaminant levels throughout the year and, except for a few trends, theses variations cannot be predicted with certainty year-to-year or wetland-to-wetland. Isotopic compositions showed evaporation was a contributor to water loss, and thus, did impact water chemistry. Surface water nitrate concentrations ranged from <0.10 to 4.04 mg/L. The nitrate levels are much higher in the groundwater, ranging from <0.10 to 18.4 mg/L, and are of concern because they are found above the maximum contaminant level (MCL) of 10 mg/L. Atrazine concentrations in surface waters ranged from <0.05 to 10.3 ppb. Groundwater atrazine concentrations ranged from <0.05 to 0.28 ppb. The high atrazine concentrations in surface waters are of concern as they are above the MCL of 3 ppb, and the highest levels occur during the spring bird migration. Most sampled groundwaters had detectable tritium indicating a mix of modern (<5 to 10 years old) and submodern (older than 1950s) recharge. The groundwater also had differences in chemical and isotope composition, and in some cases, increased nitrate concentrations, between the two sampling periods. Modern groundwater tritium ages and changes in groundwater chemical and isotopic compositions may indicate connections with surface waters in the Rainwater Basin.