March 18 2013 07:46 AM

Novel technologies could allow us to better detect mastitis infections.

by Amanda Smith, Hoard's Dairyman Associate Editor

Mastitis has severe economic consequences costing, on average, $200 or more per case. The disease also impairs cattle well being. While prevention is preferred, there are a number of technologies that assist us in mastitis detection. Common methods include the observation of clinical signs, somatic cell count testing often done in conjunction with Dairy Herd Improvement (DHI), bacteriological culturing, and the California Mastitis Test (CMT).

"As technologies progress though, novel detection methods, such as in-line milk analyzers, are coming on-line," noted Christina Petersson-Wolfe, Virginia Tech, in her presentation on the final day of the Western Canadian Dairy Seminar. While such devices have yet to become mainstream, the products afford a reduction in labor costs for testing, along with intervention and early treatment. These in-line testing systems, she added, cost approximately $2,300 per unit installed.

Using the in-line milk analyzers installed in Virginia Tech's milking parlor, Petersson-Wolfe and her graduate student, Andrea Tholen, tackled novel research related to lactose, or milk sugar, concentration and mastitis.

Between breeds, there is little variation in milk's lactose concentration. Petersson-Wolfe speculated, though, that when a cow developed mastitis, the percentage of lactose in milk would drop. They predicted this reduction because lactose, as a sugar, would be a primary carbohydrate, or food, source for bacteria in the udder. The researchers were looking for changes in a "mastitis specific component" – a variable that would likely indicate a cow had a mastitis infection that would not be readily linked to another disease state.

The control cows in the study had a very constant milk lactose percentage. But as cows developed mastitis the lactose concentration of their milk changed. For gram-positive bacteria, lactose concentrations dropped eight days prior to clinical detection of the infection. With gram-negative infections, lactose concentrations tanked the day after onset. No growth cultures also showed a change with a slight dip in concentration the day before the clinical response was detected.

The group at Virginia Tech has also developed a table summarizing the control, prevention and treatment of common mastitis causing pathogens. This pathogen cheat sheet can be found by clicking here. Petersson-Wolfe stressed though that this is just a guideline - before proceeding with any mastitis treatment, you should consult with your veterinarian.