I know that hygienic traits are a positive thing to have in a queen, and that several queen breeders mention such adjectives in their descriptions of their queens in their sale advertisements in order to get top dollar for their queens.
So I'm wondering if those of you who buy these queens with "hygienic traits", and also do hygienic testing with liquid nitrogen, what percentage of your testing shows that your queens indeed carry a 90% or better hygienic trait? Or do you feel that for the most part, these "hygienic trait" claims are no more than advertising gimmicks to win the sale?
My understanding is that liquid nitrogen test is used to determine if the queen/bees can detect brood diseases, but not necessarily used to determine their varroa sensitive hygienic behavior.
If I was buying a breeder hygienic queen I would expect very high rate of that trait - 90%+. If I was buying an open mated daughter of a AI breeder queen, my expectations of that trait would be much lower.
Our testing protocols require that the bees remove 95% or greater of the brood from our freeze kill assay in order to be utilized in our breeding program. Testing for Hygienic behavior and VSH are very different.
Exactly. Hygienic will clean up the mess in a hive. Varoa Sensitive is totally different. Get a good magnifying glass. Find bees opening a brood cell. Open it up and check for mites. Percentage on this activity would be hard to calculate. It is part of the war on mites. I would rather have it than not have it. Pushing as hard as we can on selective breeding to only breed from queens with higher mite loads that survive winter with good populations. Its getting better every year and seeing more with daughters withstand mite loads.
As cutting edge said freeze kill assay is the basic hygienic test, part of the development of the "Minnesota Hygienic".
Look up work by John Harbo for explanations of the testing protocols for the VSH characteristics.
You have to open a lot of brood counting both total infested brood and also reproducing and non reproducing mites.
A 100% VSH queen would be one that had no foundress mites reproducing.
In a normal hive about 25% of the foundress mites are non reproductive.
Breeding for improvement would be from Queens 75% or better.