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Sex differences in the proportion of the cortex and the medulla in the chicken suprarenal.

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S E X DIFFERENCES I N THE PROPORTION O F THE
CORTEX AND THE MEDULLA I N THE
CHICKEN SUPRARENAL
F. C. S A U E R AND HOMER B. L A T I M E R
Department of Anatomy, University of Kansas
This study is an attempt to throw light on the relationship
between the weights of the cortex and medulla of the suprarenal gland of the chicken and the sex of the chicken. It has
been shown that the size of the adult mammalian suprarenal
is considerably greater in the female than in the male; that
the difference is due to the presence of a greater amount
of cortical material in the female glands ; and that a relation
exists between the quantity of the cortical substance and the
development of the secondary sex characters.
Jackson (’13) finds that in general the female suprarenals
are heavier in the albino rat. Hatai (’13) finds the suprarenals heavier in the female rats; he says: “The sex difference becomes clearly marked in rats of about 30 grams in
body weight. The difference becomes greater as the rats
increase in weight.’’ J. C. Donaldson (’19) shows graphs
which indicate that the suprarenals of the female albino rat
are about one and one-half times as heavy as those of the
male. The glands of the females were found to contain relatively less medulla than those of the males, indicating that
the difference in gross weight represents a greater amount
of cortex in the females. H. H. Donaldson (’24), in studying
the rat suprarenals, says :
The volume of the medulla relative t o the entire gland decreases
rapidly from birth to 50-100 grams of body weight, after which it
increases in the male but remains constant in the female. The
greater weight of the suprarenal in the female is therefore due
mainly to the greater weight of the cortex.
289
290
F. C. SAUER A N D H. B. LATIMER
Hill ( '30) finds that in primates, carnivores, and ungulates
at time of birth the female suprarenal is larger.
It is evident that in the mammals which have been studied,
the female has more cortical material in proportion to the
body weight than the male. However, it has been found that
there is no apparent difference in the weight of male and
female suprarenal glands in chickens (Latimer, '24). This
study is an attempt to determine whether or not there is a
difference in the proportion of cortical and medullary
material in the glands of chickens such that the female may
have a greater quantity of cortical substance than the male.
MATERIALS AND METHODS
The glands studied were taken from nineteen single-comb
White Leghorn chickens from a local poultry company.
Vigorous adults were selected, ten cocks and nine hens. The
glands of the cocks were taken between October 5 and
November 21,1929, and those of the hens between October 7 ,
and November 11, 1930, or at the same period of the year
in each case, so that any seasonal changes in the glands
would not affect the result.
The birds were killed by bleeding from the jugular veins
and the glands removed rapidly and freed from adhering fat
and connective tissue as completely as possible without injuring them. They were then dropped into Zenker's fluid in
individual weighing bottles and the weight of each gland
determined from the increase in weight of the bottle and
contents. The glands were all fixed in Zenker's and stained
with Delafield's haematoxylin and Griibler 's alcohol-soluble
eosin, 0.5 per cent solution in 70 per cent alcohol. Other
eosins tried did not give good differentiations. The procedure was the same f o r every gland, so that any difference in
shrinkage of the various materials in fixation would not affect
the result.
All of the glands were sectioned and mounted. Two were
not used, as noted in tables 1 and 2. The glands were designated by the serial number of the bird and R or L to indicate
SEX DIFFERENCES
IN THE CHICKEN
SUPRARENAL
291
right or left gland. Glands of the first two cocks were sectioned to a thickness of 7 p. All others were sectioned to
l o p . For birds 1 to 5, all sections were mounted. For the
remainder, every fifth section was mounted.
The relative volumes of the various materials in each gland
were determined by projecting areas of the stained sections
on paper, drawing the outlines of the areas of the various
materials, and then separating these and determining their
weight. Glands 6L, 6R, and 7L were sampled by setting the
mechanical stage of the projecting microscope successively
to predetermined readings which represented points distributed over the entire slide, and drawing the field at each
point. The circular field drawn was 9 inches in diameter,
and at least fifty fields were drawn for each gland. The
remainder of the glands were sampled by taking strips from
center to edge of sections spaced equally throughout the
gland. At least fifty fields were drawn for each gland. These
were rectangular, 6 x 8 inches.
The material of the areas drawn was labeled as cortex,
medulla, blood spaces, and extraneous. The latter included
the capsule, ganglion cells, fat, or any other adherent material.
I n glands 3L, 3R, and 17L lymphoid infiltration was found in
sufficient amounts to be drawn, and this was kept separate
from the other areas, but is included with extraneous material
in table 1.
The method of determining areas by weight was that used
by Jackson ( ’17) and Rasmussen ( ’28). Scammon and Scott
(’27) investigated the relative merits of a number of methods
f o r estimating areas. They found the planimetric method
good for large areas, but it was found to give large errors
when used to measure small areas, and for these the ‘area
by weight’ method was found better. As the method assumes
constant weight per unit of area, the variability of weight of
the paper was investigated. Paper of good grade was found
to have a coefficient of variation of 2.50. Eastman ‘Kodaloid,
no. 3’ was found better in this respect, having a coefficient of
variation of 1.62. Paper used for drawing the sections in
T H E ANATOMICAL RECORD, VOL. 5 0 , NO.
3
292
F. C. SAUER AND H. B. LATIMER
this study was Scriptum Ledger, 19 X 24-inch sheets, 44
pounds to the ream, from the Missouri Interstate Paper Co.
Samples 1 inch square were taken from each corner of each
sheet, dried in a desiccator, and weighed. The coefficient of
variation was found to be 1.73.
The areas corresponding to the various materials on the
drawing were cut out with scissors, placed in separate
envelopes, and dried in a desiccator over fused calcium
chloride. It was found by test that they were brought to
constant weight in fifteen hours. I n order to insure thorough
drying, all paper was left in the desiccator for at least fortyeight hours. After drying, the paper corresponding to each
material was weighed separately on an analytical balance
sensitive to 0.1 mg.
MICROSCOPIC STRKCTUBE
The suprarenal glands of chickens have cortical and medullary material intimately mixed together. So far as could be
estimated without measurement, the proportion is about the
same in all parts of the gland, peripheral and central parts
showing about the same percentage of cortex and medulla.
The arrangement of cell masses, however, is different in
central and peripheral portions and suggests that of the
mammalian gland. I n all the glands of the chickens examined
a glomerular zone resembling that of mammals in arrangement of cortical cells was distinguishable at the periphery,
The central mass of the glands has an arrangement similar
to that of the reticular zone in mammals. I n a few glands
a radial arrangement of cell columns between the central
reticular and peripheral glonierular zones is visible. It is to
be noted that in mammals the arrangement described applies
to cortex with no admixture of medulla, while that in the
chicken applies to a mixture of the two kinds of cells.
I n the peripheral part of the glands the cortical cells are
arranged in columns and folded layers. The cortical cells in
this region are elongated, with their long axes transverse
to the plane of the column or layer. Cortical cells of the
SEX DIFFERENCES
IN THE CHICKEN
SUPBARENAL
293
central part of the gland are arranged in clumps. Medullary
cells in all parts of the gland have an irregularly rounded
shape.
RESULTS AND CONCLUSIONS
The gross body weights, the weights of the right and left
glands, and the proportions of the parts of the glands of the
nineteen chickens are given in table 1. The average weight of
the male glands is slightly greater than that of the female,
but it does not form a larger percentage of body weight,
because of the greater body weight of the males.
The weights of the paper representing the various parts of
the glands were recorded, but to save space these weights
are not given. The weights of the glands and of the parts
of the glands reduced to percentages of the gross body
weights are given in table 2. The per cent of blood and
extraneous materials is variable and not significant, since
the clotting time of chicken blood is extremely subject to variation (Thompson and Carr, '23). The averages in table 2
seem to indicate a slightly heavier female suprarenal, but
the small number of specimens does not warrant questioning
the conclusion (Latimer, '24) that the weight of the suprarenal glands is approximately the same in the two sexes,
since this difference is too small in proportion to the probable
error to be considered significant. The average actual weight
exceeded the average predicted weight (using the formula
from above paper) by 1.7 per cent f o r the males and 9.5 per
cent for the females.
The procedure used permits direct calculation of the per
cent which the suprarenal gland forms of the body weight of
the chicken. It also gives percentages by volume of the various materials in the gland. I n order to know the percentages
by weight which each material in the gland forms of the
body weight of the chicken, it would be necessary to know percentages by weight, instead of by volume, of the materials in
the gland. Since this cannot be determined, it is necessary
to make an assumption as to the specific gravity of the component materials of the glands. The assumption was made
F. C. SAUER A N D H. B. LATIMEE
t-m
9t - m2
mt-
0 0
r-d
w w
a 0
cnm
worn
a m
10+
0 0
0 0
0 0
0 0
0 0
d m
11 9 9 9 3 9 9 3 9
m o
0 0
1e
0 0
m o e w
r i m a m
3 3 99
0 0
0 0
a
1%'
iX
SEX DIFFERENCES
IN THE CHICKEN
295
SUPRARENAL
that cortex and medulla are of the same specific gravity, and
data of table 2 were calculated accordingly. The assumption
cannot introduce any serious error, as it is applied to glands
of both sexes.
TABLE 2
Entire gland, cortex, and medulla as percentages of body weight
1
No,
Entire
gland
Cortex
Medulla
.00247
.00276
Medulla
- _ _ ~
. _ _ _ ~
._
1L
1R
.0060
.0067
.00176
.00232
2L
2R'
.0039
.0034
.00178
.00130
......
3L
3R
.0033
.00,i3
4L
4R
-
11R
.0035
.00219
.00175
......
12L
12R
.0069
.0073
.00281
.00308
,00219
.00263
.do178
.00249
.00091
.00122
13L
13R
.0038
.0034
.0014B
.00183
.00119
.00088
.0043
.0038
.00251
.00219
.00105
.00122
14L
14R
.0052
.0063
.00223
.00290
.00182
.00230
5L
5R
.0032
.0024
.00186
.00155
.00082
.00061
l5L
15R
.0062
.0037
.00238
.00189
.00113
.00086
6L
6R
.0074
.!I068
.00179
.00195
.00251
.00318
16L
16R
.0067
.0051
.00231
.00256
.00170
.00111
7L
7R
.0058
.0054
.00257
.00273
.00156
.00174
17L
17R
.0072
.0069
.00316
.00392
.00152
.00143
8L
8R
.0071
.0049
.00245
.00212
.00241
.00163
18L
18R
.0064
.0073
.00363
.00490
.00141
.00147
9L
9R
.0047
.0061
.00251
.00237
.00144
.00171
19L
1SR
.0054
.0056
.00320
.00359
.00084
.00091
......
......
.00129
_ _
.00211:
.00006
,00144
.00164?
,00012
.0073
10L'
.0038
10R
~Average .00510:
.00022
~
' Pathological,
.
Average
I
1
~-
~
.005733
.00020
.00204
.00071
-~
~-
.00276:
.00014
.0014Ri.
.00009
~-
.-
not used.
The difference between the mean percentage weights of
the cortex in the two sexes is 0.00065, or a difference of 31
per cent of the smaller percentage. Using the formula given
by Dunn ('29) for determination of the probable error of
the difference, we have 0.00065 0.00015, or a probable error
a little less than one-fourth the difference. While a larger
296
F. C. SAUER AND H. B. LATIMER
ratio of difference t o probable error is t o be desired, the
result would justify at least a tentative conclusion that the
female domestic fowl actually has more cortex in proportion
to body weight than the male. A larger number of specimens
would permit a more definite conclusion.
I n the male chickens the percentage which cortex forms of
the body weight is less variable than either the gross weight
of the gland or the per cent of cortex in the gland. The
coefficients of variation are : cortex as per cent of body weight,
18.7; per cent of cortex in the gland, 25.5; and gross weight
of suprarenal, 30.5. So far as the male glands are concerned,
the weight of the cortex is fairly constant, and variations in
the gross weight of the gland are due mainly to a variable
amount of medulla. The male cortex as a per cent of body
weight is less than half as variable as that of the female.
The greater variation in the per cent of cortex in the female
suggests that the amount of cortex may vary at different
periods of ovulation. The standard deviation of the per cent
of cortex is 0.00039 for males and 0.00086 for females.
Nothing is known of the history of the birds, other than that
they appeared to be in good health when they were killed.
The most important conclusion to be drawn from this study
is that which pertains to the relative amount of cortex, as a
per cent of body weight. The result would indicate that
chickens resemble mammals in having a larger per cent of
cortex in the female, and it explains the correspondence of the
gross weight of the suprarenal in the two sexes as being due
to a smaller per cent of medulla, approximately offsetting
the larger per cent of cortex, in the female.
SUMMARY
1. The female chicken has approximately 30 per cent more
suprarenal cortex, in proportion to its body weight, than
the male, although the gross weight of the glands is about
the same in the two sexes.
2. The amount of suprarenal cortex is much more variable
in the female than in the male, suggesting a physiological
variation.
SEX DIFFERENCES IN THE CHICKEN SUPRARENAL
297
3. The suprarenal of the chicken shows a configuration of
cell masses of mixed cortical and medullary material, suggesting in general appearance that of the cortical zone of
mammals.
4. The weight of the suprarenal gland was not found to
be significantly different on the two sides in either sex.
BIBLIOGRAPHY
DONALDSON,
H. H. 1924 The rat. The Wistar Institute.
J. C. 1919 Relative volumes of cortex and medulla in the adrenal
DONALDSON,
gland of the albino rat. Am. Jour. Anat., vol. 25, pp. 291-298.
DUNN, HALBERTL. 1929 Application of statistical methods in physiology.
Physiol. Rev., vol. 9, pp. 275-398.
HATAI,S. 1913 On the weights of the abdominal and thoracic viscera, the sex
glands, and the eyeballs of the albino r a t (Mus norvegicus albinus)
according to the body weight. Am. Jour. Anat., vol. 15, pp. 87-120.
HAYS,V. J. 1924 The development of the adrenal glands of birds. Anat. Rec.,
vol. 8, pp. 4 5 1 4 7 4 .
HILL, W. C. 0. 1930 Observations on the growth of the suprarenal cortex.
Jour. of Anat., vol. 64, pp. 479-502.
JACKSON,
C. 31. 1913 Postnatal growth and variability of the body and various organs in the albino rat. Am. Jour. Anat., vol. 15, pp. 1-68.
1917 Effects of inanition and refeeding upon the growth and
structure of the hypophysis in the albino rat. Am. Jour. Anat., vol. 21,
pp. 321-358.
1919 The postnatal development of the suprarenal gland-and the
effect of inanition upon its growth and structure in the albino rat.
Am. Jour. Anat., vol. 25, pp. 221-289.
LATIMEEL,
H. B. 1924 Postnatal growth of the body, systems and organs in
the single comb white Leghorn chicken. Jour. Agri. Research, vol. 29,
pp. 363-397.
1925 The relative postnatal growth of the systems and organs
of the chicken. Anat. Rec., vol. 31, pp. 233-253.
1927 Correlations of the weights and lengths of the body, systems,
and various organs of the turkey hen. Anat. Rec., vol. 35, pp. 365-377.
LATIMER,H. B., AND J. A. ROSENBAUM1926 A quantitative study of the
anatomy of the turkey hen. Anat. Rec., vol. 34, pp. 15-23.
PANKRATZ,
D. S. 1931 The development of the suprarenal gland of the albino
rat, with a consideration of its possible relation t o the origin of fetal
movements. Anat. Rec., vol. 49, pp. 31-50.
RASMUSSEN,ANDREWT. 1928 The weight of the principal components of the
normal male adult human hypophysis cerebri. Am. Jour. Anat., vol.
42, pp. 1-27.
SCAMMON,
R. E., A N D G. H. SCOTT 1 9 i 7 The technique of determining irregular
areas in morphological studies. Anat. Rec., vol. 35, pp. 269-277.
298
F. C. SAUER AND H. B. LATIMER
THOMPSON,T. J., AND I. L. CARR 1923 The relation of certain blood constituents to a deficient diet. Biochem. Jour., vol. 17, pp. 373-375.
VINCENT, SWALE 1912 Internal secretion and the ductless glands. Edward
Arnold.
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