1.     Only use spring water provided in the lab (Poland Spring or Ice Mountain), not distilled water or tap water.

2.     Keep Dugesia japonica (small brown) at 22°C.  Dugesia dorotocephala (large brown), Phagocata gracilis (black), and Procotyla fuviatilis (white) are kept at room temperature, 25°C.

3.     Do not cross-contaminate the species.  D. japonica may be especially susceptible to pathogens that could live in the other species’ colonies.  Use separate utensils (new pipettes, etc.) for each species and wash your hands if they have been in contact with any colony’s water.

4.     Appropriate cycle of light (9:00 am – 6:00 pm) and dark (6:00 pm – 9:00 am) in a day prompts smooth expansion of the worm population.

5.     All colonial worms are fed on Tuesday and require an additional water exchange on Friday. 

6.     Experimental animals in isolation require NO feeding, but must have a water exchange twice a week (on Tuesday and Friday).

To feed the worms:

1.      Purchase fresh chicken liver and chop it into teaspoon-sized aliquots. Wrap each in a small piece of aluminum foil and store in a freezer-safe plastic container in a freezer.

2.      On feeding days, thaw one aliquot of chicken liver for each colony container, at room temperature.

3.      Cut up the chicken liver on the cutting board. Remove the tough fibers in the liver.

4.      Throw little bits of liver into the worm trays.

5.      Pipette water up and down a few times to free up the worms so they find the food.

6.      After almost the worms finish eating (it takes for 3-4 hours), but before the water gets dirty, BE SURE to exchange their water. If you forget this, the worms will die.

To exchange water:

1.     Remove the liver with the pipette. Don’t disturb the worms, until you remove almost of the liver. If you disturb the worms, it will be difficult to remove the liver.

2.     Push the floating worms down to the bottom of the tray by pipetting and wait for the worms to settle down. Pour out the water carefully into a bucket.  If some worms start floating, pick them up (return into the trays later) or push them down by pipetting.

3.     Pour a small amount of fresh water into the tray. Wash the bottom of the tray by pipetting. If some particles of liver are remaining, remove them as completely as you can. And then pour water out carefully.

4.     Refill with fresh water and label the container with the date.