Evaluation of a simple sedimentation method (modified McMaster) for diagnosis of bovine fascioliosis.

A coprological sedimentation method is evaluated for quantification of egg shedding in bovine faeces. Through the inclusion of different number of Fasciola hepatica eggs in negative faeces, egg recovery rate and the sensitivity of the method were determined. The mean egg recovery rate of the technique was 76.72+/-15.42%. The sensitivity of the method was 33.3% whenever eggs/g of faeces (EPG) are less than 1.5 and 100% for higher values. To improve the diagnostic accuracy with this technique, it is advisable to increase the sample from 10 to 30g of faeces when manipulating low egg shedding, which allowed for a sensitivity of 83.3%. Regression equations were calculated to quantify the relationship between the number of recovered and incorporated eggs.