Worm recovery from cups

Materials:

• Cups
• Faeces
• Physiological solution (0.9% NaCl)
• Tap water

Procedure

Incubation of faeces

• Around 20 g of faeces are added to a cup
• The faeces are stirred with tweezers to make the sample less compact
• The cup is incubated at 28 °C for 1 week

Worm recovery

• The cup is filled with water (200 mL)
• One half of a petri dish is placed on top. The cup with the petri dish is then turned upside down.
• The cup is left at room temperature ON, to allow the dry material to soak water and deposit on the bottom.
• The following day the cup with the petri dish are tilted to recover the liquid, which contains the worms
• The worm solution is left in the fridge for 3 hours, to allow a complete deposit of the worms.
• Most of the supernatant is removed, and the worm solution can be stored.

Worm purification

Materials:


• Loose cotton
• Pasteur pipettes
• 15 mL falcon tubes
• Physiological solution (0.9% NaCl)

Procedure

Debris removal

• Cotton is added to a pasteur pipette to obtain a filter around 1 cm wide
• Some drops of physiological solution are added to each pipette, to soak the filter
• One worm solution deriving from each isolation protocol is added slowly making sure it doesn't flow through
• The solution is left in contact with the filter for 30 min
• Around 5 mL of physiological solution are added on top of the filter, until all the liquid has run through. Lifting the pipette from the liquid in the bottom of the falcon can help in this process.
• Purified worm solutions are stored at 4°C to leave the nematodes to settle. When sample is needed, supernatant is removed to concentrate the samples