Hi Florian,

In principle I should not answer as I am not a specialist on that matter but I found your observation quite intriguing/interesting so... It may sounds like half a joke but can you imagine putting some ink on the tip of the tail and then leave the mouse walk for a given time on a sheet of paper - mice with "weak tail" will leave more tracks behind them that you can certainly scan and quantify using some kind of image analysis software.

In addition, and considering that mice use their tail to control their balance pretty much like a circus performer use a pole, you may want to look at how your mice perform in a balance test?...

Norbert

Thanks, Norbert!

I'm thinking of getting ink already ;) But I was looking through different papers and simply couldn't find this test. As we are absolutely not equipped for phenotyping, I'd need to get creative for the balance test. What I know is people let mice walk over beams/blanks or put them on something rotating.

At this stage you probably don't need to worry too much about using a validated test or investing in specific behavior equipement. To assess tail weakness try with ink and see how it goes, you should be able to get an idea already, and after all I don't think this approach is biased in any ways - it should be relatively simple and straightforward. As for the balance test, simply let your animals walk on a string - it is a possibility that those with weak tail will simply fall off or lose their balance - just count how many times they get upside down for a given time. It is cheap and fast and if you see something obvious then you can look for better behavioral assessments.

Good luck, it sounds you have something cool in your hands!