2018-2019 Faculty Research Grants

Kathy Koudele, Tim Newkirk and Melissa Poua (Agriculture, Medical & Laboratory Sciences)

The Correlation between the Milk Somatic Cell Count and the Differential Leukocyte Count in the Blood of Cows that have a Positive Milk ELISA Test for Antibodies to the Bovine Leukosis Virus

Bovine leukosis (BL) is a naturally-occurring transmissible retrovirus disease of cattle caused by the bovine leukosis virus (BLV) that is considered to be of economic importance in the international trade of animals and animal products. 89% of dairy herds in the U.S. have at least one infected animal. Presence of the virus is determined by measuring the BLV antibodies in a cow’s milk using an ELISA test. About 30-40% of cows that are infected show an increase in the quantity of white blood cells (WBCs) circulating in the bloodstream, however, the characterization of the types and ratios of WBCs has not yet been examined. It is hypothesized that some of these excess WBCs would end up in the udder since the lactating udder receives a very high blood flow, and this would therefore contribute to the elevated somatic cell count (SCC) in the milk. (For every liter of milk produced, 500 liters of blood circulate through the udder.) Therefore, a cow that is positive for BLV is likely to also have an elevated SCC in her milk.