[Determination of fibrinogen levels in the horse with the heat-precipitation methods of Schalm and Millar].

The purpose of this study was to investigate the usefulness of two heat-precipitation techniques (Schalm- and Millar-method) as screening tests to measure plasma fibrinogen concentration in horses. Based on the measurement of samples from 108 different horses, the coefficient of correlation (CC) for the relationship between the results with the Schalm- and with the reference-method (Jacobsson) were much lower (r = 0.78) than between the Millar- and Jacobsson-method (r = 0.94). Furthermore the Schalm-method was less precise as reflected by the greater coefficient of variation (CV, within-run precision) with a sample of low-limit fibrinogen concentration (CV = 47.4 %) and with a sample of high fibrinogen concentration (CV = 35.6 %) than the Millar-method (CV = 11.1 resp. 2.9 %). In 40 healthy horses, aged 3 to 19 years, fibrinogen values ranged from 1.82 to 4.94 g/l (2.5-97.5 %-quantil). The Millar-Method is recommended as a simple and suitable heat-precipitation assay for fibrinogen determination in the horse.