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Qn« Insemination With Spenn From Sevoral Drones 
When neither individual mating nor long productive life is desired, 
several drones from the same source can be used, making one injection con- 
sisting of at least 2»5 inm,^ of semen. Viith this procedure it is almost 
certain that none of the queens will begin laying as partial or complete 
drohe layers, and if kept in nuclei most of them will last a season with- 
out becoming drone layers* One additional carbon dioxide treatment is 
necessary to start egg laying. 
Two or More Inseminations 
To fill the spennatheca sufficiently to carry a queen through a season 
in a large colony, two or more inseminations must be made, each consisting 
t>f 2»5 mm.' of semen* An additional carbon dioxide treatment is not neces- 
sary* Hundreds of queens mated two or three times have performed as well 
as naturally mated queens* 
A still greater number of sperms cern be made to reach the spermatheoa 
by giving three or four inseminations with 2*5 mm*' of semen* They are 
given on alternate days beginning on the fourth day or, in the case of foxir 
inseminations, they may be started the third day to reduce the likelihood 
of interference with the beginning of oviposition. 
Considerable variation can be expected in the percentage of laying 
queens obtained* In one group of 95 queens inseminated three times, 83 per 
cent started laying; however, results as low as 60 percent can be 4xpected 
occasionally* In general, the more inseminations made the more chances of 
injury and consequent loss. Practically all queens that sxirvive to laying 
age will begin laying* 
Table 1 compares the number of sperms in various artificially inseminated 
and naturally mated queens* These data are taken from Several experiments* 
Note that the coefficient of variation decreases as the number of insemina- 
tions is increased, and that it is lower in some of the inseminated queens 
than in those naturally mated. Note also that the minimiim in the group 
inseminated three times is higher than the minimum in the naturally mated 
queens, and that the average and maximum in the group inseminated four 
times are nearly as great as the corresponding figures for the naturally 
mated queens* 
The performance of artificially inseminated queens compares very well 
with that of naturally mated queens* In 1945 queens inseminated artificially 
three times were compared with queens of identical parentage mated naturally 
at an isolated mating station* Surplus honey produced was about the same 
for the two types of matings, as already reported by Roberts (j) , Brood 
production and brood quality were not significantly different, but survival 
to the end of the season was somewhat lower in the artificially inseminated 
group* 
