# Home VSH Testing



## JWChesnut (Jul 31, 2013)

http://www.extension.org/pages/30984/selecting-for-varroa-sensitive-hygiene#.Ug21M1MQ9y8


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## Michael Palmer (Dec 29, 2006)

The hygienic response for brood removal, and VSH removal of mite infested brood are not the same.


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## JSL (Sep 22, 2007)

Yeah, what Mike said. 

Hygienic behavior for controlling brood diseases involves the liquid nitrogen frozen brood test or some derivation of it.

Selection for VSH behavior is going to set you back a little more money and time as a scope is very helpful and a good bit of time to do the dissection or brood and counting.

Joe


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## Chemguy (Nov 26, 2012)

liquid nitrogen is nice because it freezes quickly, then boils off quickly. If you're wanting to test for brood removal, perhaps dry ice would be an acceptable substitute. It can be pulverized into a granular powder easily by placing into a sturdy container, and whacking it with the top of a claw hammer or piece of wood. Shaking the container the way one would flip an egg in a skillet without a spatula will raise any un-pulverized chunks to the surface for another round of pulverization. Or, you could sift through 1/4" hardware cloth. 

If you do use the dry ice, know that because it takes longer to sublime than liquid nitrogen does to boil, the area that will be frozen will be a bit larger than the area of application.


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## Michael Bush (Aug 2, 2002)

> perhaps dry ice would be an acceptable substitute.

When discussing this with Marla Spivak she said dry ice did not work well. It often did not kill the brood. If you really don't want to buy the dewar and the liquid nitrogen, I'd either do the pin prick method (which Marla says isn't as good because there are two behaviors involved and one is uncapping which you skip with this method) or cut the section out and freeze it in your freezer overnight, thaw it, and then put it back in the hole you made and see how fast they uncap it.


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## Specialkayme (Sep 4, 2005)

Marla Spivak recommended against using dry ice at last year's EAS in Vermont. Instead, she suggested using a round cookie cutter to punch out a section of capped brood from a frame (of wax foundation without wires), put it in a freezer overnight, then put it back in place the next day (after thawing).

She actually recomended using the cookie cutter over liquid nitrogen for people that weren't doing dozens of tests a day. She said that she had to use the nitrogen because she couldn't wait 24 hours and then revisit the same site.


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## Specialkayme (Sep 4, 2005)

You beat me to it Mike, lol.


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## Adam Foster Collins (Nov 4, 2009)

Mike Palmer and Joe Latshaw - yes. You are correct and that was my error in typing the original post. I should have said "hygenic testing" and not "VSH testing".

True. Hygenic and Varroa Sensitive Hygiene are not the same.

Adam


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