Hygenic test results on breeders

[cklspencer]

I've done the freeze test one many of my breeder hives but I saw a clip in a video the other day where they use a needle and poke the larvea under the cap to kill it and than come back 24 hours later to see if they cleaned it out. What would be the differance between the poke test and the freeze test or do they show the same thing?

[JBJ]

I have heard there are two sets of genes involved, one for uncapping and one for cleaning, and that the piercing of the caps can skew the tests.

[JBJ]

What is interesting to me is that you said "We arrived at a very hygienic bee by selecting for Varroa tolerance". My understanding is that Marla Spivak and Gary Reuter started the other way, breeding for hygienic bees by using the frozen NO2 test because of the strong correllation of hygienic behavior with bees that remain free of AFB. Yet they make no claim that MH queens are varroa resistant. What percentage of your breeders were that hygienic - if you don't mind sharing.
So, in addition to your bees having hygienic capabilities I suspect they have other positive attributes that make them varroa resistant.

I have heard that also. I have also heard the developers of the VSH and SMR traits ended up with very hygienic bees in the end working from the other direction. Of the ones we have tested, about half were 90 to 100 percent and the other half was all over the place. We plan to monitor mite levels in all but have been grafting off the ones that got 100% lately. The others may still have valuable traits if they test well on the sugar roll later in the week.

[bend or]

Is there a reason to use liquid N2 vs a "freeze spray" like caned air turned upside down? It seems like it would have the same result and be more portable, and using a ring would still be able to control the area affected.

[Adrian Quiney WI]

JBJ, it will be interesting to see how there results match up: Your hygienic bees roll test versus the less hygienic ones.

[sqkcrk]

Is there a reason to use liquid N2 vs a "freeze spray" like caned air turned upside down? It seems like it would have the same result and be more portable, and using a ring would still be able to control the area affected.

Could be just as effective I guess, having no experience w/ either. All I know is liquid nitrogen is standard operating procedure, tried and true. So, no one sees the need to change. Try it and let us know how well it works. You may be on to an alternative method. Or it could have been tried and rejected for some reason or other.

[canoemaker]

I attended a queen rearing workshop with Dr. Larry Connor this May and asked him about using the canned coolant, like for freezing off warts. He said it would be really expensive, and not very effective. It wouldn't get the brood cold enough for long enough to kill it. He gave an example of how tolerant the brood is by telling about an alternative method to the LN2. If you use wax foundation, you can cut out a 3"x3" plug of brood and put it in the freezer for 24 hours, then place it back in the brood frame. Then you can do your 24 hour hygenic test. He said someone he knew took their brood out of the freezer after 24 hours and it was still alive! They must have soft ice cream! Anyway, the liquid nitrogen must be the gold standard for freezing and killing the brood. If your home freezer is really cold, you can try the plug method.

[pine_ridge_farms]

I've seen the pictures around but how is it done. Do you just pour some liquid nitrogen in the pvc and let it sit for X minutes?

Thanks

[Adrian Quiney WI]

Dan, I'm with you. I would like to see a youtube video, or Beesource pictorial on how it's done and a description of where the supplies came from and the cost.

[pine_ridge_farms]

I've seen the pictures around but how is it done. Do you just pour some liquid nitrogen in the pvc and let it sit for X minutes?

Thanks

Anyone? Thanks

[Rusty Hills Farm]

I believe this poster is what you are looking for. It's from the Bee Lab and shows you how to test.

HTH

Rusty

[pine_ridge_farms]

I believe this poster is what you are looking for. It's from the Bee Lab and shows you how to test.

HTH

Rusty

Thanks Rusty!