Collaborative evaluation of rolling ball viscometer for measuring somatic cells in abnormal milk

Area of Science:

• Dairy Science
• Analytical Chemistry
• Veterinary Diagnostics

Background:

• Somatic cell count is a key indicator of milk quality and udder health.
• Current instrumental methods and the Wisconsin mastitis test are standard diagnostic tools.
• The Ruakura rolling ball viscometer offers a potential alternative for milk analysis.

Purpose of the Study:

• To evaluate the Ruakura rolling ball viscometer for somatic cell measurement in milk.
• To compare its performance against established instrumental methods and the Wisconsin mastitis test.
• To assess the impact of replacing Teepol reagent with Wisconsin mastitis test reagent.

Main Methods:

• Comparative analysis of the Ruakura rolling ball viscometer with instrumental methods and Wisconsin mastitis test across three laboratories.
• Evaluation of reagent substitution (Teepol vs. Wisconsin mastitis test reagent) within the viscometer.
• Assessment of repeatability and reproducibility for all tested methods.

Main Results:

• The Ruakura rolling ball viscometer demonstrated satisfactory repeatability and reproducibility.
• Instrumental methods yielded higher readings compared to the viscometer and Wisconsin mastitis test.
• Utilizing Wisconsin mastitis test reagent enhanced the viscometer's repeatability and reproducibility.

Conclusions:

• The Ruakura rolling ball viscometer is a viable method for somatic cell analysis in milk.
• The Wisconsin mastitis test reagent improves the viscometer's performance.
• Further standardization efforts are recommended to harmonize viscometer readings with instrumental methods for broader adoption.