On Sept. 28 Allen Dick wrote:
 
<Do you think there is any real advantage in selecting larvae at 12 hours
<compared to 36?  If not, then one could adjust emergence dates a bit to
<avoid weekend emergence.  Being somewhat unknowledgeable about such
<things, we always use the youngest available.  Is that important?
 
<Perhaps we could discuss incubation temperatures at some later time.  My
<measurements don't agree with the published numbers.  The books refer to
<92F.  I measure 95.5F  +/- 0.5F.  I've heard rumors that some breeders
<adjust hatching time by controlling temperature.  True?  False?
 
Laidlaw in Contemporary Queen Rearing says "The queen rearer should choose
larvae as young as can be transferred to the queen cell cups with reasonable
ease and without injury.  Larvae 36 hours old should be the maximum age for
grafting."  the age given in the different bee books varies from 12 to 36.
Ruttner says that it has not been proven that 36 hours old larvae develop into
queens inferior to to queens rered from 12 hour larvae.  I suggest staying on
the safe side.  Transferring older larvae in the sole purpose of retarding
hatching does not sound to me like the good option.  I graft with 12 hours
larvae.  You can transfer younger larvae but it takes more skill and time.
 
Hatching of the cells could be retarded by controlling the temperature of the
incubator.  I have retarded cells for as long as 4 days and still most of them
hatch.  Nevertheless this is not a recommandable practice.  The longer the cells
are retarded, the lower the acceptance in the colonies you introduce them to.
Even celll introduced on the 12th day after grafting give significantly worst
results than cell introduced on the 11th.  The schedule I prefer is the
following:  graft on day 0 from 12 h larvae, pull the cells from the cell
builders on day 10 ans keep them in an incubator overnight at 85-87 degrees
Fahrenheit, introduce them in the colonies on day 11.  You can pull them and
introduce them on day 10 also but the cells are a little more fragile then and
more suceptible to be affected by the cold or heat and by shocks.
 
If you want weekends off the best option is to avoid grafting on tuesdays,
wednesdays and thursdays for an introduction on the 11th day or avoid wednesday
and thursdays for an introduction on the 10th.
 
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
'''
' JEAN-PIERRE CHAPLEAU                               eleveur de reines/bee
breeder '
' Chapleau & Courtemanche enr.
'
' 1282, rang 8, St-Adrien, Quebec, Canada, J0A 1C0
'
' [log in to unmask]                               tel./phone (819)
828-3396 '
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
'''