Xenopus laevis

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We had some discussion on our existing feeding regime for our frogs as well as diets we use. We would like to review and compare with what other facilities do.

I would be grateful if people could let me know, frequency of feeding, approx. amounts per feed per frog or x frogs and what type of feeds you offer.

Our growing adult xenopus are fed 3 times per day and eat roughly 7-10 pellets each per feed. Growing males have roughly 5-7 pellets. Our older male females will only consume around 5 pellets each and are fed 1 - 2 feeds per day. They're all fed Monday to Thursday. We feed them Skretting Horizon 2.3mm Sinking Pellets.

This is our current feeding regime:

Feed type - LabDiet Aquatic blend 5mm (9GJN)

Frequency - We feed them twice a week, usually on a Tuesday and Friday, subject to bank holidays etc.

Amount - As a guide we use 1g of food per female frog and 0.5g of food per male frog.  This usually equates to 1  x small bijou per tank of 3 females or tank of 8 males.

I would like to ask you if anyone is working with xenopus and which is the euthanasia method used. The use of MS-222 takes long in an emergency or when time is scarce.

In one aquarium, as a Schedule 1 method, they use an overdose of anaesthetic: MS-222 in water  and confirmation of death later and pithing.

The problem is that the MS-222 in water could take 1-2 hours when used at a max of 4 gr/l concentration.

Do you think is possible to sedate the xenopus in a water bath of MS-222 at a 2 gr/l concentration and after immerse the frogs in a higher MS-222 concentration of for example 10gr/l to speed the euthanasia process?

I use 5gr/l and if it freshly made it is quite quick.

Please be sure to buffer/pH neutralize your MS222 - particularly if you are using higher doses. Otherwise it will likely be unpleasant for the xenopus due to the pH. The buffering should also improve the induction time. Not all directions for use of MS222 included directions for buffering when I looked into this.