Division I.2.1 Cytology (imprint cytology)

After drying digestive gland tissues on absorbent paper, several imprints shall be made on a glass slide. Slides shall be air-dried, fixed in methanol or in absolute ethanol and stained using a commercially available blood-staining kit such as Diff-Quik®/Hemacolor®, in accordance with the manufacturer's instructions. After rinsing in tap water and drying, the slides shall be mounted with a cover-slip using an appropriate synthetic resin. The slides shall be observed first at × 200 magnification and then under oil immersion at × 1 000 magnification.

A positive result shall be the observation of cells ranging in size up to between 30 to 40 μm. The cytoplasm stains basophilic, whereas the nucleus stains eosinophilic. Pale halos around large, strongly stained (refringent) granules and, in larger cells, cell within cell arrangements are observed.

The technique is not parasite species specific.