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North High Xenopus laevis tadpole Care Sheet:
** Make sure to write down what you did and the date you did it in the composition notebook. Please also document it on the Excel sheet so it doesn’t get done twice!!**
Water Composition for Moderately Hard Water (MHW): 95 mg NaHCO3, 3 mg MgSO4, 0.4 mg KCl, 50 mg CaSO4, and 50 mg CaCl2 in 1 L deionized water
Tank Setup: At an angle (on 500 mL beakers) with aeration system (through pipettor glass tips) , 6 L MH water, 30 tadpoles (initially), respective Isoxaben treatment
Isoxaben Treatments: Scott and I will make these to be added to the water. You will not be dealing with the full concentration of the Isoxaben at any time.
CONCENTRATIONS:
Documentation:
Dates and what you did (feed, clean, etc)
Changes in shape (try to use Gosner stages)*
Time to metamorphosis
Size at metamorphosis (S-V length and mass, make sure to include units)
Mortalities
** Make sure to document what tank you are documenting!!
Clean tanks 2 times per week- Full tank cleans
1. Have water ready to be used (mixed MHW)
2. Have container with treated water ready to place tadpoles in
- Recommend about 1 liter of water (can pour water and tadpoles directly back into tank—total 6 L water in tank)
3. Remove tadpoles with minimal touching (try pour method)
4. Pour out remaining water
5. Rinse with hot tap water and scrub with respective scouring pad. (Do not use any cleaning agents or use pad for cleaning other items. This pad should be used only for its tadpole tank and can be rinsed with hot tap water after cleaning is done.)
6. Do final rinse with hot tap water to remove any debris left by pad.
7. Refill tank with about 5 L treated (MHW with respective Isoxaben treatment water and then place tadpoles (and the water they are in) into cleaned tank. MAKE SURE NOT TO SWITCH TANKS—tadpole are to be returned to their original tanks!
DAILY MAINTENANCE:
· Feed daily. Tadpole food is made by suspending food in water. ¼ T in 1 cup treated water. We recommend using a blender to truly suspend the food or a container with a lid and shake vigorously for a few minutes. Remember that these tadpoles are suspension feeders. Feed until water is cloudy but not dense. (We fed 80 mL to 120 tadpoles). Too much food can suffocate them and change the water quality for those that live. As tadpoles die or metamorphose, you can decrease this food amount.
· Pipette out debris on bottom of tanks. This can be poured down the toilet when finished.
· Try not to clean the tanks after using soap or lotion on your hands. The materials left on your hands can be put in the water and change the water quality.
· Document each day if you have mortalities (write down the number of deaths and remove them) or changes in shape. Refer to Gosner stages to determine where they are at. When the tadpoles start to reabsorb their tails, they stop eating (they use the energy from the tail to continue development—at this stage they get lungs, change their mouthparts, and obvious physical changes take place). Document how long it takes since you started until they reabsorb their tail completely.
· Document any morphological anomalies. In the last batch of tadpoles without any chemical treatment, we produced a 3-legged frog and a five-legged frog. Document these abnormalities. Watch for tadpoles with these features—sometimes they don’t make it to metamorphosis but we should still document them!
· Those that have metamorphosed need to be removed from the tank with tadpoles. They are then to be weighed and measured. Feed them the pellets that we provided and place them in a tank with just a few centimeters of water. They are fully aquatic so they don’t need any land areas to climb up onto, but do like refuge areas (plastic aquatic plants work fine!). You can document their behavior until you return them to me, if you want.
· We work hard to not kill the tadpoles or the froglets. Once metamorphosed or when we decide the experiment is finished, they will be donated to a local pet store to be sold or given to schools to use as an educational tool.
· HAVE FUN!! This is a great opportunity and hard work but it pays off!