Application of Immunohistochemistry and ELISA for the Diagnosis of Neospora-Infected Cattle

Studies were undertaken to adapt diagnostic methods for use in our laboratory for detection of Neospora sp. infection in cattle. An immunohistochemical (IHC) test was used for detection of Neospora sp. antigen in tissues of aborted bovine fetuses. Neospora sp. antigen was detected most frequently in fetal brain tissue. Polyclonal antibodies were tested for specificity and sensitivity of the IHC. Sera were obtained from Neospora sp. infected dairy herds for use as positive and negative controls in the continuing development of an enzyme-linked immunosorbent assay (ELISA).

Split Nitrogen Application Trial

Farmers understand it is best to apply nitrogen to the crop at or right before rapid growth occurs. However, 100 percent in-season nitrogen applications are faulted because of potential for unfavorable weather conditions delaying applications and subsequent deficiency occurring. This trial looks at how split nitrogen applications can be used to address environmental risks of pre-plant nitrogen application as well as unfavorable application conditions in-season.

Impact of Liquid Swine Manure Application and Cover Crops on Ground Water Quality

The primary objective of this project was to determine the impact of appropriate rates of swine manure applications to corn and soybeans based on nitrogen and phosphorus requirements of crops, soil phosphorus accumulation, and the potential of nitrate and phosphorus leaching to groundwater. Another purpose of this long-term experimental study was to develop and recommend appropriate manure and nutrient management practices to producers to minimize the water contamination potential and enhance the use of swine manure as inorganic fertilizer. A third component of this study was to determine the potential effects of rye as a cover crop to reduce nitrate loss to shallow ground water.

Corn Response to Sulfur Application Rate

Historically, sulfur (S) application has not been recommended on Iowa soils for corn and soybean production. Soils supply, or a combination from sources such as soil organic matter, profile sulfate, manure, and precipitation have met crop S needs. However, over the past few years, S deficiencies in alfalfa and corn have been documented. Large crop yield responses have been measured in some fields containing soils with low organic matter, side-slope landscape position, or coarse soil texture, especially in northeastern Iowa. The objective of this study was to determine S response in corn and soybean in north-central Iowa.