At this year’s National Mastitis Council in Fort Worth, Texas, attendees learned about a new on-farm technology that allows dairy producers to accurately “see” mastitis before symptoms appear, using the Milk Leukocyte Differential (MLD). Rudy Rodriguez, founder of Advanced Animal Diagnostics, Durham, N.C., said similar white blood cell differential technology has long been a tool in human and companion animal medicine.

The dairy industry can now use this technology to detect subclinical mastitis early and accurately – and by the quarter – with the QScout™ MLD test. The below press release, outlining Rudy’s presentation, reveals how understanding the cow’s immune system response to infection provides the most accurate picture for diagnosing hidden mastitis on the farm.

Rather than simply looking at somatic cell count (SCC) – the sum of all body cells and inflammatory cells found in milk – Rudy recommends looking at the differential cell count, a separate count and proportion of each type of white blood cell, including macrophages, lymphocytes and neutrophils.

“By counting, measuring and assessing the ‘first responders’ of the cow’s immune system, it is possible to more accurately detect infection,” he said. “Composite milk samples can blend away subclinical mastitis hiding in a quarter, but QScout MLD looks at each quarter individually for elevated neutrophil levels that signal infection.”

Rudy brings more than 30 years of experience in human and companion animal medical devices development to the dairy industry and says a better understanding of the dynamics mastitis could be accomplished by specifically measuring the rise and fall of the types of white blood cells in the milk.

Accompanying Rudy was Dr. Mitch Hockett, Advanced Animal Diagnostics’ director of farm trials and technical marketing, who shared the results of a selective dry cow trial in which cows diagnosed with QScout MLD at dry off were treated with antibiotics only if at least one quarter was infected. When this group was compared with cows that were blanket treated with antibiotics in all quarters, no statistical difference existed between the two groups in culture positive infection rates or SCCs 10 days after calving or in clinical events, culls or other health events through 150 days in milk.