shows cooling of mousemet probe after preheat to skin temperature
shows force rise of mousemet probe
shows probe heating to thermal threshold
shows cooling of mousemet probe after preheat to skin temperature
MouseMet Electronic von Frey
EvF hasn't always lived up to its name. Some early systems were expensive, difficult to use and not quite appropriate for this delicate measurement.
MouseMet is different...
Invented in 2014 by a specialist in force measurement and a leading veterinary anaesthetist, MouseMet EvF bridges the gap between traditional von Frey filaments and digital electronics:
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Accurate and sensitive: 0.05gf -7gf range
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Easy to use: Ergonomic, rotary force gauge with a flexible, filament-like tip
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Affordable: Prices start at £990
Accurate:
MouseMet EvF is a custom designed force gauge for measurement in the range of 0.05gf -7gf. So it compares directly from the 0.07g filament to beyond the 6g filament.
To put this into context: you wouldn't use a one pint jug to measure out a teaspoonful, would you? But some EvFs have a force range of 500 or even 1000gf which, in the same way, is just not appropriate for a measurement that rarely exceeds 5gf. So we designed MouseMet, from first principles, to be sensitive and accurate in the force range required. And that's all it does. It doesn't measure beyond 7gf.
And then for rats, where the force range is higher (but still only up to 80 or 100gf, depending how hard your rats are), we didn't just adapt; we kept the same rotary design but built another new force gauge (yes...it's called RatMet!).
For both instruments, any difference you see in magnitude of treatment effect, compared to filaments, is because of the differing diameter of the filaments. This is entirely to be expected, and quantifiable.
Easy to use
MouseMet is comfortable; it's tiring to hold a filament or an EvF in the air, above the bench, and then to raise it under the mouse's foot at a steady rate. Hand tremor is a real problem and leads to "touch-on" responses, especially in long testing sessions.
So MouseMet has a rotary action: to operate, put your elbows on the bench and then turn the big grippy handles to bring the tip (0.3mm) into contact with the plantar surface. It feels like it's on a tripod and, with a starting force of just 0.05g, the chance of a touch-on response is much reduced.
Then twist the handles further to apply the stimulus. At the nociceptive threshold, just remove the tip and press the green button to display the result.
This data was kindly provided by the University of Queensland and shows the reduction in mechanical threshold at 5 and 24 hours on 6 mice after VCR injection.
If you buy MouseMet runs, it's even easier as the stand is height adjustable in steps of 20mm and there's a completely clear line of sight at the bar level with no metal frame around the edge.
MouseMet EvF is supplied with 2 probes (one for each range), optimised for this delicate measurement: the arm is 1mm carbon fibre rod with a flexible probe tip (again to prevent touch-on responses from side to side hand tremor).
We take continuity of data very seriously, so we supply a calibration arm and weight. The arm will also allow you to compare your existing von Frey filaments directly with MouseMet.
Affordable
Best of all, MouseMet EvF costs just £990, when bought on line with a credit card. With a set of filaments costing around £500 and other EvF systems costing £2000 or more, MouseMet EvF really is a cost effective solution for mechanical nociceptive threshold testing on mice.
Fill in the form at the foot of the page and we'll send you a quote and a payment link, including shipping and any accessories you need.
MouseMet EvF is often bought in conjunction with our hot probe This offers advantages over the "Hargreaves" or hot plate test as our hot probe is used in the same runs as our EvF. So you can halve the acclimation time and reduce the stress for the mice. The hot probe has exactly the same rotary action as the EvF but with a 2mm thermal probe on the end of the rotating arm. It is brought into contact with a force of under 1g (again to avoid touch-on responses) and heating starts and stops automatically. And, to complete the set, we also offer a cold probe with the same footprint.
All stimullii are applied automatically and the threshold recorded on removal. And all three, EvF, Hot and Cold can be used in the same mouse runs.
This vastly reduces acclimation time and stress for the mice: a big contribution to the 3Rs
"MouseMet EvF provided our behavioural endpoint to quantify tactile allodynia and its attenuation in this mouse CIN model. It is a terrific piece of instrumentation that has lead us to a novel approach for treating CIN"
Dr K Sufka
Professor of Psychology and Pharmacology
University of Mississippi
ABOUT TOPCAT METROLOGY LTD
Topcat Metrology develops and supplies novel measurement equipment for veterinary research. The company's original product, developed twenty years ago, was a thermal threshold testing system. The product range today now includes mechanical threshold testers, remote-controlled systems (allowing completely free-ranging subjects during a test) and hand-held mechanical testers, suitable for clinical use.
GET IN TOUCH
Gravel Head Farm, Downham Common
Little Downham, Ely
CAMBS UK
+44 7739 913696