4.5.1 fixatives: glacial acetic acid, or alcohol-formalin-acetic acid (AFA) (85 mL 85% ethanol, 10 mL formalin, 5 mL glacial acetic acid)

4.5.2 preservatives: 70% ethanol, or alcohol-glycerol (9 parts 70% ethanol, 1 part glycerol)

4.5.3 clearing agents: glacial acetic acid, or glycerol, or xylene

5.1.1 Candling light table

The recommended light table for candling (10.3, 10.13) should have at least two 20 watt "cool white" fluorescent tubes. The light source should be held by a rigid framework below a white, translucent acrylic plastic or other suitable material with a translucency of between 45-60%.

This working surface should be approximately 30 x 60 cm and 5-6 mm in thickness. The average light intensity should be between 1500 and 1800 lux as measured 30 cm above the center of the acrylic sheet. Overhead illumination should be at least 500 lux. Adequate results may also be obtained in the laboratory using a simple photographic light table.

Candling works equally well with fresh or previously frozen fillets. The efficiency of the candling technique is largely dependent upon the thickness of the fillet being examined (10.13). Large, thick fillets, therefore, may pose a particular problem due to the increased production costs and loss of value involved with slicing such fillets. The candling technique is generally considered to be a costly and inefficient means of detecting and removing parasites from fillets. The technique is also limited in that it cannot distinguish between live and dead parasites.

5.1.2 Place fillet on a light table and examine for the presence of tightly coiled, encapsulated larvae, which will appear as dark spots. Unencapsulated larvae may also be observed on the surface of the fillet.

5.1.3 Use forceps to transfer any visible worms to a dish of normal saline.

5.2.1 Wear an ultraviolet resistant face shield or safety goggles.

5.2.2 In a darkened room, hold UV light approximately 10 cm above surface of fillet and examine for fluorescent worms. The colour of the fluorescence aids in a preliminary identification. Anisakis and Pseudoterranova larvae fluoresce a bright bluish-white colour while Contracaecum larvae fluoresce yellow (10.9). As with candling, this procedure will not distinguish between live and dead parasites.

5.2.3 Use forceps to transfer worms to a dish of normal saline.

5.3.1 Transfer up to 200 g of fish tissue to a U.S. Standard No. 4 sieve (or equivalent sized kitchen sieve) positioned in a large funnel or other vessel. Attach tubing to the neck of the funnel and close off tightly with a tubing clamp.