In-house validation of a method for detection of animal meals in ruminant feeds by microscopy

The aims of this work were the optimization and the in-house validation of a qualitative method for detection of meat and bone, steamed bone, blood, poultry offal, feather and fish meals in ruminant feeds by microscopy. Specificity, detection limit and fitness for purpose were evaluated by procedures with reference materials, sample blanks and samples spiked with each analyte at 0.025%, 0.05%, 0.10%, 0.20%, 0.40% and 0.80%, in at least three independent replicates. Detection limits were 0.05% for meat and bone, steamed bone, blood, feather and fish meals and 0.10% for poultry offal meal.