From Wikionchus

Worm Food

Pristionchus pacificus is kept on standard NGM agar plates seeded with OP50. OP50 is a uracil-auxotroph of Escherichia coli and therefore only grows as long as uracil is provided by the NGM agar. OP50 does therefore not overgrow the plates and forms a nicely translucent lawn of bacterial cells. This essential for everyday binocular low-magnification microscopy.

Pristionchus pacificus feeds on OP50 in the lab. It is not known yet what the natural food sources for Pristionchus are in the wild but it has been shown to feed on different bacteria, fungal hyphe, fungal spores, protists and even other nematodes.

Contaminations are a big problem of stockkeeping and pose a potential threat to sick mutant strains. Contaminations are usually worst during the humid seasons of the year and in Tuebingen this is summer and fall.

Mites: If you see little monsters with 8 legs on your plates, mites invaded your stocks. This is very dangerous: not only do they eat your worms if they are really hungry, they might also carry worm-larvae and eggs to another plate, another box, another room. Thus, if your worms have mites, a) seal all affected plates with parafilm and autoclave (you can transfer some worms before to keep the stock, but take care not to pick mite-eggs). b) wash the box with the affected plates (and the shelf where it was standing) with ethanol and c) inform your colleagues and ask them to check their stocks.

Cleaning contaminated worm stocks

There are two commonly used methods to clean contaminated stocks.

• Bleaching worms
• Treatment with antimycotic substances (like for example Nystatin)

Links

• Back to Pristionchus pacificus Protocols page