Reference system for somatic cell counting in milk

Abstract

With some analytical parameters, certified reference materials are lacking and the reference method shows limited performance. Somatic cell counting in milk is a clear example. It is one of the most frequently performed measurements, estimated at over 500 000 000 tests/year world wide. It serves as an indicator for the udder health status of lactating animals, is relevant in food legislation, in payment of raw milk, and also has a considerable impact for farm management and animal-breeding programs. The analytical performance of nowadays fluoro-opto-electronic routine methods in terms of precision is superior to the reference method based on microscopy. Laboratories have therefore adopted various solutions for anchoring their counting level. It is there that a reference system approach can serve to optimally safeguard comparability of routine testing results in laboratories world wide. A reference system is characterized as a systematically developed anchoring system that is fed by different types of information from various sources, that is, measurements on reference materials, reference method analysis, and routine method results. A joint Project Group of the International Dairy Federation and the International Committee on Animal Recording has been given the task to design a workable global reference system for somatic cell counting in milk. This paper describes the structure and the functioning of such a reference system, a plan for the implementation and the responsibilities of the involved stakeholders in safeguarding its functioning. After approval in IDF and ICAR, the resulting proposal is to be offered for adoption by concerned governmental and nongovernmental bodies worldwide.

A robust segmentation method for counting bovine milk somatic cells in microscope slide images

“…On the other hand, it is possible to detect mastitis and the severity of it in milk samples by SCC performed via DMSCC. This is the reference methodology adopted by the International Dairy Federation and used even for electronic equipment calibration (Orlandini and van den Bijgaart, 2011).…”

Probabilistic comparison and assessment of proficiency testing schemes and laboratories in the somatic cell count of raw milk

“…A reference system is characterised as a positioning system fed by different types of information from various sources-that is, from reference materials, reference method analysis, routine method results and PT results of laboratories operating in a laboratory network structure [10].…”

“…The approach was developed in the framework of the SCC Reference System Working Group (International Dairy Federation [IDF] and the International Committee on Animal Recording [ICAR] [5,10]) by the participating organisations. The basic assumption is that the PT schemes are conducted according to recognised guidelines such as the Harmonized Protocol [11] and ISO 13528 [12] or ISO 5725 [13] in order to compute performance characteristics such as z-scores, repeatability and reproducibility standard deviations.…”