as did Rughand Clugston (1955)forFundulughetero
SPINCREASE IN. RADIORESISTANCE OFFISH
as did Rugh and Clugston (1955) for FPundulus hetero-
ported on several stages of development of the eggs
TO LETHAL DOSES WITH ADVANCING
EMBRYONIC DEVELOPMENT
of the loach, Misgurnus fossilis through late blastula.. Golvinskaia and Romashov's usefu] review of
the literature appeared in 1958. Rugh (1954) gave
pertinent data for amphibian development.
Interpre-
ER
API SHAS BONHAM and ARTHOR DW ELAND
tation of the findings of all of these authors dis-
arecaren ca cea ACT OO SNE
e Lahorators of Radiation Brotaiwy, Tnucersitn of Weshington,
.
Seattle. Wavkington
,
INTRODUCTION
Fos
papers exist on the radioresistance of the
goof fishes at vartous developmental stages.
ander (1:54) showed the resistance of rainbow
ut cegs to increase with advancing age of embryo,
closes a relationship of radioresistance to stages of
embryonic
development,
that
is common to fish and
to
at least some other organisms. Thus it is our objective to determine the rate of increase in radio-
resistance of fish eggs with advancing embryological development, to compare this rate with some
other type of organism, and to quantify the relationship if possible.
We present one block of
Welander's heretofore unpublished data on irradiated
Silver salmon eggs and refer to published literature for the rest of the data.
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é
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80
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50 |
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ces
20 40
80
0 20
40
bolas dg
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thes see
ootay
60
_
a:
3
©
20
DAYS
40
60
AFTER
©
20
40
60
0
20
40
6
80
!60
i20
140 I60
FERTILIZATION
on at Mittoeeve percentage mortality of egys and young of silver salmon in 23 experiments involving
Shown ay tu BO dayeees of development.
t
CPt
s,
Numbers along the curves are doses in roentgens.
and to 150
days in experiment 23.
:
WMortali-
Below the abscissa are indicated, by an X,
At the
Urrateation. are given the stage of development and the percentage of incubation completed
irradaadr
3
‘On, anand, by a horizontal line, the maximum duration of the hatching period.
ft wach seer
thet lme e
NaF
ma
TV ES
ARC
353