210 PACIFIC SALMON FISHERIES, 
HANDLING EGGS IN HATCHERY.¢ 
At some of the Bureau’s stations where salmon eggs are handled it was the custom 
until a few years ago to ‘‘bury”’ the eggs or leave them undisturbed (aside from picking 
once the day after spawning) for two or three weeks after putting them in the baskets. 
The result was that they were in some instances literally buried under and in such a 
mass of mud and sediment that many eggs were killed. Discontinuance of the prac- 
tice resulted in a very appreciable improvement. 
When the water is so turbid as to cause a heavy deposit of sediment, it is better to 
go over the eggs occasionally, even through the critical stages of development, or 
until the line of the fish is well formed. Of course the eggs must be handled with 
utmost caution at all times, but owing to their extreme sensitiveness during the two 
or three days following the closing of the blastopore and until a perceptible curve 
shows in the tail, they should be left entirely untouched. It soon becomes easy to 
determine the stage of an egg’s development by holding it up to the light between the 
thumb and forefinger. In the absence of cautious and skilled operatives and unless 
the water is roily for an extended period, it is undoubtedly better to let the eggs 
remain undisturbed until the curvature of the tail is visible to. the unaided eye. 
The accumulation of a moderate coating of sediment which readily washes off is not 
injurious. In a few instances it has become necessary to handle the eggs during the 
tender stage to arrest the spread of fungus, but where the water supply is reasonably 
well adapted to fish-cultural purposes such a course is rarely if ever necessary. 
REMOVAL OF DEAD EGGS BY THE USE OF SALT SOLUTION. 
Among the most noteworthy advances in fish-cultural methods during the last few 
years has been the use of salt as an aid in the removal of dead eggs. The development 
of this process has extended over a period of several years, but it is more during the 
last year or so through the efforts of L. E. Baldridge, of the Yes Bay station, that it 
has reached a high degree of efficiency. 
Compared with the time-honored process of picking by hand, there are marked 
advantages in using the salt solution, and chief among these is the great saving of labor. 
It is estimated that if the eggs happen to be of not more than mediocre quality it 
would take at least 20 pickers to remove as many dead eggs as could 2 men using the 
salt solution. Moreover, the operation is much more thoroughly performed in the 
latter process than is possible in picking by hand. 
Another advantage of using the solution is that it is possible thoroughly to clean 
the eggs. This greatly reduces any loss through contamination and infection resulting 
from the decomposition and fungous growths which inevitably follow the long-con- 
tinued presence of dead eggs that in the hand-picking method frequently escape 
‘attention. Even when utmost care is taken to pick out all dead eggs, fungoused 
masses will occasionally appear. This condition is rarely observed when the salt 
solution has been used, and it undoubtedly means that in the aggregate many eggs 
are saved. Still another point in favor of the solution, it is generally believed, is 
that it acts as a tonic or stimulant to the good eggs while at the same time as a deterrent 
to the growth of fungus. Again, in picking by hand there is apt to be loss by move- 
ment of the eggs during delicate stages of development; and the oft-repeated insertion 
of egg tweezers, which are bound to touch other eggs, undoubtedly at times results 
in injury. 
Recent experience has demonstrated that the solution may be applied effectively — 
to eggs freshly taken as well as those in more advanced stages of development. 
aF¥ish culturein Alaska. By WardT. Bower. Alaskan fisheries and fur industries, 1911. United States 
Bureau of Fisheries, document no. 766, p. 81, 82. 
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