Queen cell failure rate

[foghornleghorn]

What's an acceptable failure rate for queen cells, was pulling out cell holders today and out of 33 there was8 with a dead queen inside. Some looked like they had dwv. All were put in nucs/mini hives day before hatching straight from cell raiser.

 

[For want of a better word]

50 - 95% for imported exotics.... 20 % on an average for Natives.

Yeghes da

 

[B+.]

What's an acceptable failure rate for queen cells.

You'll get failures at each stage. This is normal. You can refine your process and correct as many of the shortcomings as you can, but, you'll still have some failures.
I am lucky enough to have an incubator. I can collect the cells as soon as they are sealed and keep them in the incubator until the queen emerges. I can then check the queen (particularly her legs and wings). Any that don't look right get squished straight away. It has to be done.
I had one queen that emerged yesterday. One of its back legs was stiff. It didn't walk properly. Now, even if a nuc had allowed her to live (which is doubtful), how would she lower her abdomen into a cell to lay an egg if she didn't have full use of her legs?
If someone tells you they have no failures, don't believe them. As for an "acceptable failure rate, it stands to reason that we should try to minimise failure. However, if you get enough mated queens to satisfy your needs then, that is acceptable.

 

[B+.]

50 - 95% for imported exotics.... 20 % on an average for Natives.

I'm not sure where your numbers come from. I think failure rates depend more on the ability of the person doing the queen rearing than on the race.

 

[foghornleghorn]

You'll get failures at each stage. This is normal. You can refine your process and correct as many of the shortcomings as you can, but, you'll still have some failures.
I am lucky enough to have an incubator. I can collect the cells as soon as they are sealed and keep them in the incubator until the queen emerges. I can then check the queen (particularly her legs and wings). Any that don't look right get squished straight away. It has to be done.
I had one queen that emerged yesterday. One of its back legs was stiff. It didn't walk properly. Now, even if a nuc had allowed her to live (which is doubtful), how would she lower her abdomen into a cell to lay an egg if she didn't have full use of her legs?
If someone tells you they have no failures, don't believe them. As for an "acceptable failure rate, it stands to reason that we should try to minimise failure. However, if you get enough mated queens to satisfy your needs then, that is acceptable.

Does that 25% or so for unhatched cells sound high is what I was really wondering? How would that compare to anyone else?

 

[B+.]

Does that 25% or so for unhatched cells sound high is what I was really wondering? How would that compare to anyone else?

I would consider 8/33 a high failure rate. I have 2/32 in my incubator at the moment that I expected to emerge overnight. Our situations are different though.

 

[Finman]

Once I caged queen cells at the out temp of +8C. All died = 100%.


.

 

[Michael Palmer]

I would consider 8/33 a high failure rate.

As would I. Queen pupae with DWV? Did they get too hot or too cold? I've had plenty of cell builders with mite loads and never seen DWV in queen pupae.

 

[protheroe]

I've had a few with non developed wings.temperature at certain point in development I believe.i haven't seen it for a couple of years using incubator.
Last batch of 25 cells I lost one queen.fully developed with side of cell open and it wasn't another queen that killed her as they were all caged cells

 

[foghornleghorn]

This is the sort of state the dead cells were in, it would have been up to about 20°c when they were in so would have thought ideal conditions with a box bursting with bees and well fed.
Have 27 hatching Tuesday/Wednesday so might put them all in the incubator and make sure they hatch before wasting bees on them.

 

[foghornleghorn]

Checked the unhatched cells of my last batch and found varroa in most of them. Stuck in a tray of apiguard and another lot of cells so hopefully that will be the problem solved.

 

[Carsten]

Forget the books. It is all about temperature.
Never go higher than 34,5-34,7C Higher than 35C kills them or invalidates. Hatching is too fast (10-11 days)
At 33,5-34,5C, they hatch after 11-12 days.
If you remove them from cellbuilder as fast as possible they hatch 100% - and all in perfect health. Remember, a queen hatch when 16 days old - according the books Try it

 

[B+.]

Forget the books. It is all about temperature.
Never go higher than 34,5-34,7C Higher than 35C kills them or invalidates. Hatching is too fast (10-11 days)
At 33,5-34,5C, they hatch after 11-12 days.
If you remove them from cellbuilder as fast as possible they hatch 100% - and all in perfect health. Remember, a queen hatch when 16 days old - according the books Try it

I had 114 A.m.c. cells emerge in my incubator this year alone. It is set at 35 degrees C and 50% humidity. The alarm goes off if it exceeds 1 degree or 1% either way from that setting. I don't think a little variation would kill them but too much certainly would.
I move the cells to the incubator when they are sealed but I don't get 100% (1/20 failed in the last batch).

 

[For want of a better word]

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0050150

May be of interest... I am investigating the wooden cages... at present "holding" virgin queens in plastic queen excluder cages in mini nucs ( Keilers) prior to AI ( ie NOT intr cages that exclude workers)

Still loosing some queens to absconding and bloody wasps!

Nos da

 

[foghornleghorn]

Forget the books. It is all about temperature.
Never go higher than 34,5-34,7C Higher than 35C kills them or invalidates. Hatching is too fast (10-11 days)
At 33,5-34,5C, they hatch after 11-12 days.
If you remove them from cellbuilder as fast as possible they hatch 100% - and all in perfect health. Remember, a queen hatch when 16 days old - according the books Try it

The hatching rate went up to around 90% after I dosed them for varroa so did seem to be the major cause of poor hatching in my case anyway

 

[wightbees]

My last batch of 17 and 1 Died in the cell for what ever reason. These where all cage cells raised in a hive.

 

[SDM]

I'm not sure where your numbers come from. I think failure rates depend more on the ability of the person doing the queen rearing than on the race.

His numbers come from a.deep seated Prejudice and a desperate need to make natives more appealing imo

 

[Teemore]

Have undertaken 126 grafts from my own bees so far this season so I'm not doing this on a big scale. From these, 94 queen cells were drawn out and capped. Of these, 8 failed to emerge. There were no varroa in the cells that did not emerge. I have given perhaps half of these queen cells to other beekeepers and have not kept track of their success beyond emergence.

I may switch back to using an incubator to give me an opportunity to assess queens post emergence and prior to popping them into mating nucs.

I have higher losses of queens from mating nucs (not absconding) so I need to change how I manage my Kielers and Apideas. I may be crowding too large a number of queens from the same batch into an area in my queen rearing apiary so I am tweaking layout to compensate.

What sort of queen loss rates do forumers get with their mating nucs?

 

[madasafish]

.

What sort of queen loss rates do forumers get with their mating nucs?

Zero - once I started adding enough bees.

My mating nucs - approx 12 - are spread out on poles in our veg garden, between bean poles/raspberry canes.. Nothing is ground based as we have badgers - which like bee brood.

No clear runs for birds or hornets (not that we have hornets.. too cold).

Pictures show in June: much more overgrown now!

 

[Teemore]

I currently have about 25 mating nucs in an area of my garden, a little over 200 square metres in size with semi mature trees surrounding. We are surrounded by farmland with some natural old riparian woodland (hazel) close by. All mating nucs are in shade under/in hedges and trees. I deliberately avoided placing any mating nucs in my other apiaries this year.

I do not consider that my queen losses from the mating nucs have anything to do with a lack of bees in the mating nucs as I have lost queens from newly stocked apideas as well as apideas that have already produced one or two mated and laying queens. These apideas have plenty of bees in them. I cut out brood and rewax frames in addition to swapping out brood to stop them becoming overcrowded.

Too many mating nucs in the one spot with queens being attracted back to the wrong mating nuc? Thoughts please?

I have 12 selected (full) stocks approx 200m away from the garden and queen mating site. I am keeping mating nucs away from full stocks in case queens are attracted back to them on their way back from orientation/mating flights.