NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
76
SEASONAL VARIATION IN SEMEN QUALITY
[Vol.
XXII, Part II,
TABLE I
Monthly averages of 'reaction-time', semen and blood characteristics of the bulls and the meteorological data during the entire experimental period
Reaction-time (in seconds)
Appearance of semen
Initial motility of spermatozoa
Volume of semen (in c.c.)
pH of semen
Sperm concentration (in millions
per c.c. of semen)
Total number of spermatozoa (in
millions)
Percentage of abnormal sperma-
tozoa
Haemoglobin (gm. per 100 c.c. of
blood)
Percentage of cell volume
Air temperature (°F.)
Percentage of humidity
Rainfall (in inches)
1945-46
J
91.46
M
4.19
2.05
6.18
698.54
1,318.67
4.63
8.79
45.65
60.9
59
0
F
40.63
M
3.85
2.52
6.15
625.0
1,549.51
5.88
8.91
45.48
67.1
61
0
M
65.63
M
3.63
2.22
6.32
788.33
1,772.95
5.71
8.82
43.49
73.3
34
0.01
A
69.12
M
3.65
2.03
6.3
658.33
1,417.39
5.13
8.89
42.92
84.8
42
0.68
M
69.73
Th. M
3.54
2.17
6.21
591.66
1,338.65
2.63
8.77
43.27
88.5
47
1.72
J
117.50
Th. M
3.08
2.40
6.24
532.29
1,467.31
3.71
8.29
40.04
89.5
61
4.59
J
48.58
Th. M
3.48
2.44
6.32
564.79
1,492.77
2.58
7.89
38.14
83.7
85
22.21
A
81.71
Th. M
3.21
2.33
6.11
511.70
1,275.68
4.38
7.82
32.99
84.9
79
8.59
S
97.0
Th. M
3.75
2.00
6.12
561.87
1,178.99
4.79
7.37
35.52
82.7
83
13.94
O
52.29
M
3.69
1.93
6.19
609.08
1,165.85
8.63
7.63
36.96
77.1
68
5.03
N
141.75
M
3.75
1.91
6.24
680.88
1,296.33
5.33
7.88
37.56
68.6
66
0
D
95.83
M
3.92
1.87
6.23
676.88
1,309.17
5.63
8.12
42.01
59.1
67
0
1946-47
J
62.96
M
3.23
2.27
6.51
720.0
1,713.84
9.25
8.90
45.33
58.9
71
1.32
F
82.13
M
3.38
2.03
6.52
698.13
1,482.89
7.00
8.85
43.99
64.2
63
0.75
M
33.46
M
3.38
2.24
6.29
704.79
1,422.13
3.96
8.76
41.76
75.3
45
0.96
A
112.33
M
3.38
2.20
6.20
720.42
1,450.25
5.79
9.34
44.95
86.7
22
0.00
M
36.17
M
3.42
2.00
6.26
665.63
1,272.13
6.33
9.59
45.95
92.7
31
1.01
J
30.0
M
3.13
2.02
6.33
670.83
1,195.84
5.04
8.70
42.67
93.5
50
5.25
J
76.46
M
3.10
2.31
6.37
636.00
l,428.36
3.25
8.25
40.13
85.6
81
16.89
A
103.28
Th. M
3.56
2.82
6.33
569.58
1,834.62
5.63
7.90
38.14
85.9
80
6.11
S
54.67
Th. M
3.29
2.33
6.34
500.42
1,180.97
3.96
7.42
38.99
85.4
65
4.01
0
51.53
Th. M
3.40
2.30
6.34
456.46
1,069.31
5.75
8.18
40.73
79.0
72
5.17
N
78.21
M
3.54
2.49
6.33
711.04
1,721.14
5.75
8.24
41.55
68.9
64
0.04
D
91.88
M
3.27
2.14
6.48
676.42
1,386.99
6.33
8.07
41.03
61.7
62
0.21
M=Milky
Th. M=Thin milky
JUNE, 1952] D. P. MUKHERJEE AND P. BHATTACHARYA 77
RESULTS
Data regarding the average 'reaction-time', semen and blood attributes of the
bulls together with the meteorological data of each month are presented in Table I.
Examination of the data reveals that there did not exist any relationship between
the 'reaction-time' and the quality of semen produced by the bulls in each month.
Average 'reaction-time' in 1945-46 was the shortest in February and longest in
November. There was, however, no appreciable difference between these months
in majority of the semen characteristics. In 1946-47 the 'reaction-time' was the
lowest in June and highest in April. The over-all quality of semen during these
two months of that year were diametrically opposite; semen samples of April
were decidedly superior to June samples.
Colour of the semen samples produced by the bulls during the experimental
period were either yellow or milky white. Yellow samples were the characteristic
feature of the bull 187. They were thin in consistency and were of low sperm con-
centration. The semen samples produced by the remaining five bulls were generally
milky white in colour. The consistency was either very thin giving a cloudy appear-
ance or like that of milk, or thick giving a milky creamy appearance. Creamy
samples, of which there were a few, contained very high concentration of sperma-
tozoa. Milky samples were of higher sperm concentration than cloudy or yellow
samples.
In working out the average colour and consistency for the month as presented
in the table, the characteristics of the majority of the samples for the month were
only considered. From the table it is apparent that sperm concentration of thin
milky samples ranged from 456.5 to 591.7 millions per c.c. and that of milky samples
from 609.1 to 788.3. There was no marked monthly variation in the initial motility
of spermatozoa and the volume of semen. The latter, however, showed some de-
crease from October to December during the first year of the experiment.
No marked monthly variation was noticed in pH. The average pH value of
semen samples during the first year was lower than that of the second year.
In 1945-46, sperm concentration and haematological constituents decreased
from May to September and in 1946-47 from July to October. Meteorological
data of these periods show high air temperature associated with high relative humi-
dity and rainfall.
Total number of spermatozoa was calculated by multiplying the total volume
with the sperm concentration. Inspection of the data presented in the table shows
that in this characteristic there existed variations from month to month. These
variations were statistically analysed. The, implication of the analysis has been
discussed later on. In the first year, percentage of abnormal spermatozoa was
minimum during May to July and maximum during October. In the second year
it dropped down to minimum in March, July and September and maximum was
reached during January.
Average monthly variations in 'reaction-time', in semen characteristics and
in blood constituents are presented in Plate IV, and that of air temperature, relative
78
SEASONAL VARIATION IN SEMEN QUALITY
[Vol. XX11, Part II,
humidity and rainfall in Plate V. From Plate IV it is apparent that the curve
for 'reaction-time' is not uniform and does not show any definite seasonal trend.
Initial motility curve shows a tendency to follow the curve for sperm concentration.
The curve for volume reached its peak in August 1946 and minimum in December
1945-46. The curve for pH shows an opposite trend to- that of sperm concentra-
tion. The curves for sperm concentration, haemoglobin and cell volume run parallel
to one another and show definite seasonal trends. From Plate V it is evident that
with the rise of air temperature, relative humidity and rainfall, there was decrease
in the sperm concentration and in the two blood constituents studied. Low air
temperature associated with high humidity as found in the month of December
of both the years had depressing effect on sperm concentration and blood consti-
tuents. The curve for total number of spermatozoa does not uniformly resemble
the curve representing sperm concentration. The curve for abnormal spermatozoa
has two peaks, one in October 1946 and the other in January 1947.
TABLE II
Average 'reaction-time', semen and blood characteristics of the bulls and the
meteorological conditions in different seasons
Reaction time (in seconds)
Colour and consistency of semen
Volume of semen (in c.c.)
Initial motility of spermatozoa
pH of semen
Sperm-concentration (in millions per c.c.)
Total number of spermatozoa (in millions)
Percentage of abnormal spermatozoa
Haemoglobin contents in blood (grams per 100
c.c. of blood)
Percentage cell volume
Percentage of humidity
Rainfall (in inches)
Air temperature (0°F.)
Autumn
(August
to
October)
73.42
Th. M.
2.28
3.48
6.25
534.85
1,284.24
5.52
7.72
37.22
74.5
7.14
82.95
Winter
(November
to
January)
93.63
M.
2.12
3.60
6.32
693.96
1,457.86
6.15
8.33
42.19
64.83
0.26
62.95
Spring
(February
to
April)
67.23
M.
2.21
3.53
6.29
699.17
1,515.85
5.58
8.93
43.76
44.5
0.40
75.23
Summer
(May
to
July)
63.07
M.
2.22
3.29
6.28
610.20
1,365.85
3.92
8.58
41.70
59.16
8.45
88.91
Th. M.=Thin milky
M.=Milky
PLATE IV
[Indian J. vet. Sci., Vol. XXII, Part II]
Monthly variations in ' reaction-time ', semen and blood characteristics.
[Indian J. vet. Sci., Vol. XXII, Part II]
PLATE V
Monthly variations, in average air temperature, humidity and rainfall.
June, 1952[ D. P. MUKHERJEE AND P. BHATTACHARYA 79
Table II shows variations in average 'reaction-time', semen and blood character-
istics of the. bulls and the meteorological conditions during the four seasons. The
figures given in the table are the averages for. two consecutive experimental years.
Perusal of the table reveals that there did not exist any correlation between the
'reaction-time' and the quality of semen in different seasons. 'Reaction-time'
was longest in winter and shortest in summer. Very little difference in volumes
and pH of semen existed during the seasons. Sperm concentration, total number
of spermatozoa, haemoglobin and cell volume contents of blood were lowest in
autumn and highest in spring. Initial motility of spermatozoa was lowest in summer
and highest in winter. Percentage of abnormal spermatozoa was conspicuously
low in summer. Relatively, little difference was observed among the remaining
three seasons. In winter and spring when the semen was rich in sperm concentra-
tion, the samples had a milky appearance. In summer and autumn the ejaculates
contained lesser number of spermatozoa and their appearance varied from milky
to thin milky. Relative humidity and rainfall were highest in autumn and lowest
in spring. Average air temperature in autumn was almost as high as in summer.
Air temperature in spring was moderate.
Statistical analysis of the results
The data summarised in Table I and II, and the average quality of semen pro-
duced by the individual bulls during the entire experimental period have been
subjected to analysis of variance to determine whether or not the variations as
found in semen qualities, blood constituents and meteorological data were real or
due to chance. The summary of the results of the statistical analysis has been
presented in Table III.
TABLE III
Summary of the analysis of variance of semen and blood characteristics of the bulls
and meteorological data
Factors for analysis
Reaction-lime
Volume of semen
Initial motility of spermatozoa
pH of semen
Sperm-concentration
Total number of spermatozoa
Source of variation
Between
bulls
**
**
**
**
**
**
Between
years
°
°
**
**
°
°
Between
seasons
°
°
°
°
**
°
Interaction
between
seasons
and years
°
°
°
°
°
°
Between
months
within
seasons
°
°
°
**
°
°
3 A
80
SEASONAL VARIATION IN SEMEN QUALITY
[Vol. XXII, Part II,
TABLE III—contd.
Factors for analysis
Percentage of abnormal
spermatozoa
Percentage of haemoglobin
Percentage of cell volume
Average humidity
Average rainfall
Average temperature
Source of variation
Between
Bulls
°
**
**
..
..
..
Between
years
°
**
**
°
°
°
Between
seasons
**
**
**
*
*
**
Interaction
between
seasons
and years
°
°
*
°
°
°
Between
months
within
seasons
°
**
**
°
°
°
**Significant at one per cent level.
*Significant at five per cent level.
°Non-significant.
The results show that in all the characteristics of semen and blood, excepting
in the percentage of abnormal spermatozoa there was highly significant variation
among bulls. In other words, the variations observed were so great that differences
due to chance were less than one per cent. Between the two experimental years
of 1945-46 and 1946-47, the semen characteristics observed, excepting the initial
motility of spermatozoa and pH of semen, were due to chance variations. Haemo-
globin as well as cell-volume contents of blood were highly variable between years.
Among seasons, variability in initial motility was just significant, whereas the
variations in sperm concentration, percentage of abnormal spermatozoa, haemo-
globin and cell-volume were highly significant. Cell-volume varied due to inter-
action of seasons and years. Among months within seasons, highly significant
variations were found in pH of semen and blood characteristics.
Analysis of variance of the meteorological data was carried out between years
among seasons and interaction between seasons and years. It will be seen from the
table that air temperature variation among seasons was highly significant. There
was, however, significant variation in relative humidity and rainfall.
To test the differences between significant and highly significant factors as
presented in Table III, critical difference (C.D.) of the variable factors at 5 per cent
level of probability was worked out and the results are presented in Tables IV to
VI. In each of the tables average figure under the same bar did not vary at 5 per
cent level. Table IV shows C. D. of variable factors among bulls.
June, 1952] D. P. MUKHERJEE AND P. BHATTACHARYA 81
TABLE IV
Critical difference of five per cent level of variable factors between bulls
Reaction-time (in seconds)
Volume of semen (in c.c.)
Initial motility
pH of semen
Sperm concentration (in millions per c.c.)
Total number of spermatozoa per ejaculate (in
millions)
Percentage of haemoglobin (in gm. per 100 c.c.
of blood)
Percentage of cell volume
Value of C.D.
36.81
0.34
0.27
0.08
114.92
318.74
0.24
1.49
Averages of bulls arranged in ascending order
240
(42.17)
248
(1.56)
187
(2.55)
195
(6.21)
187
(308.95)
248
(690.44)
187
(8.04)
187
(39.12)
194
(52.64)
195
(2.07)
248
(3.04)
240
A(6.22)
248
(410.20)
187
(1,041.35)
200
(8.06)
248
(40.25)
248
(57.67)
194
(2.10)
194
(3.73)
200
(6.24)
200
(628.44)
200
(1,351.35)
248
(8.12)
200
(40.94)
187
(83.23)
200
(2.11)
200
(3.75)
187
(6.33)
240
(757.76)
194
(1,724.33)
195
(8.34)
195
(41.10)
195
(100.43)
240
(2.43)
240
(3.86)
194
B(6.34)
195
(806.05)
195
(1,745.32)
240
(8.70)
240
(42.90)
200
(109.94)
187
(3.00)
195
(4.02)
248
(6.39)
194
(895.83)
240
(1,882.65)
194
(9.10)
194
(43.90)
82
SEASONAL VARIATION IN SEMEN QUALITY
[Vol. XXII, Part II,
TABLE V
Critical difference at 5 per cent level of variable factors between years
Initial motility of spermatozoa
pH of semen
Percentage of haemoglobin
Percentage of cell volume
Value of
C.D.
0.12
0.04
0.14
0.87
Averages of years arranged
in ascending order
1946.47
(3.33)
1945.46
(6.22)
1945-46
(8.27)
1945-46
(40.37)
1945-46
(3.64)
1946-47
(6.36)
1946-47
(8.52)
1946-47
(42.10)
TABLE VI
Critical difference at 5 per cent level of variable factors between seasons
Initial motility
Sperm concentration per c.c. of
semen.
Percentage of abnormal sperma-
Percentage of haemoglobin in
blood.
Percentage of cell volume
Percentage of humidity
Average rainfall
Average air temperature
Value of
C.D.
0.22
93.84
1.24
0.20
1.21
18.66
6.40
7.86
Averages of seasons arranged in ascending
order
Summer
(3.29)
Autumn
(534.85)
Summer
(3.92)
Autumn
(7.72)
Autumn
(37.22)
Spring
(44.50)
Winter
(0.26)
Winter
(62.95)
Autumn
(3.48)
Summer
(610.20)
Autumn
(5.52)
Winter
(8.33)
Summer
(41.70)
Summer
(59.16)
Spring
(0.40)
Spring
(75.23)
Spring
(3.54)
Winter
(693.96)
Spring
(5.58)
Summer
(8.58)
Winter
(42.19)
Winter
(64.83)
Autumn
(7.10)
Autumn
(82.50)
Winter
(3.66)
Spring
(699.17)
Winter
(6.15)
Spring
(8.93)
Spring
(43.76)
Autumn
(74.50)
Summer
(8.45)
Summer
88.91)
June, 1952] D. P. MUKHERJEE AND P. BHATTACHARYA 85
animals improved during the second year as shown by higher haemoglobin and cell
volume contents of blood, their semen quality deteriorated as indicated by higher
pH value of semen and lower initial motility of spermatozoa. No satisfactory
explanation for this deterioration in semen quality seems possible without detailed
studies of the various contributory factors for semen production.
Critical difference of the variable factors between seasons is given in Table VI.
From the table it is apparent that there was no significant variability in the initial
motility and sperm concentration between summer and autumn. For initial
motility summer and for sperm concentration autumn was the worst season. For
haemoglobin and cell volume in blood, autumn was decidedly inferior to the rest
of the seasons. Haemoglobin varied from season to season but no significant varia-
tion in cell volume was found between winter and summer. For the two blood
constituents and for sperm concentration, autumn was the worst and spring the
best season. Autumn differed significantly from spring in relative humidity and
rainfall; these in the former season being 30.0 per cent and 6.74 inches respec-
tively more than in the latter. There was, however, no significant variation in the
average air temperature between the two seasons. It appears, therefore, that
sperm concentration in semen as well as the two blood constituents improved con-
siderably when the environmental temperature was moderate and humidity low.
TABLE VII
Percentage distribution of abnormal spermatozoa in different seasons
Seasons
Autumn
Winter
Spring
Summer
Abnormali-
ties of
head.
2.66
2.83
2.12
2.66
Abnormalities of
middle piece
Beaded
middle
piece
2.7
2.04
2.33
2.25
Other ab-
normalities
0.95
0.25
0.25
0.45
Abnormalities of tail
Tailless
12.65
8.33
8.37
11.08
Bent
tail
9.33
15.75
12.33
3.91
Coiled
tail
2.54
3.46
3.16
1.83
Other
abnorma-
lities
2.46
2.91
4.66
1.79
As regards abnormal spermatozoa, summer differed significantly from the rest
of the seasons. In summer percentage of abnormal spermatozoa was low. Per-
centage of abnormal spermatozoa during the different seasons of the year is given
in Table VII. The most common types of abnormalities have been tabulated under
different heads and those which were not common have been put under one group
' other abnormalities'. It will be seen from the table that in winter and spring ' bent
tail' spermatozoa increased considerably, whereas autumn and summer favoured
4
86
SEASONAL
VARIATION
IN
SEMEN
QUALITY
[Vol. XXII, Part II,
the formation of tailless ones. Percentage of ' coiled tail' spermatozoa was higher
in winter and spring and lower in autumn and summer. The rest of the abnor-
malities did not show any marked variation from season to season. The fall in
the percentage of abnormal spermatozoa in summer might be due to the fact that
during this season the ' bent tail' sperms were minimum although the tailless ones
were as high as in autumn.
Consideration of critical difference of pH. and blood constituents between months
has not been attempted as the samples obtained from each bull in a month were
too small to yield any valid conclusion.
DISCUSSION
As has been stated above, statistical analysis of the data on ' reaction-time'
revealed that it was not influenced by season. Salisbury [1944] also did not find
any significant monthly variation in bulls with regard to this character.
' Reaction-time' is an indication of sex desire or libido and sex vigour. Sex
desire as judged by ' reaction-time' varied considerably in bulls, but it did not
give any indication as regards their sperm production. This observation is in agree-
ment with those reported by McKenzie and Berliner [1937] in rams, and Anderson
[1939] in bulls.
Various workers have shown that sex desire in males is controlled by male
hormone (testosterone). Injection of testosterone to immature, castrated or hypo-
physectomised animals increased their sexual desire as shown by the erection of
male genitalia and increased frequency of copulation [Hamilton, 1937; Shapiro,
1937 ; Stone, 1939; etc.]. It appears therefore, that the production of testosterone
in the matured bulls of the present experiment was not influenced by such external
factors as air temperature, relative humidity and rainfall.
Volume
From the analysis of variance of total volume of semen it is seen that there was
highly significant variation among bulls in their total output of semen per ejaculate.
This character, however, was not variable from month to month or from season to
season. The present result agrees with those reported by Phillips et al. [1943],
Swanson and Herman [1944], Salisbury [1944] and Anderson [1946] but is contrary
to those obtained by Erb et al. [1943] and Mercier and Salisbury [1946].
Total volume of semen is mainly dependent on the secretions of the accessory
reproductive organs. It is now well-known that these secretions are dependent
upon testosterone liberated by the interstitial cells of the testes. The measure-
ment of the total volume of semen, therefore, as pointed out by Bogart and Mayer
[1946] reflects the functional capacity of the interstitial cells. Results obtained
in this experiment show that there was individual variation in the functional capacity
of the interstitial cells of the testes in bulls but it was not influenced by seasons.
This observation, therefore, lends further support to the view that proudction of
testosterone is independent of the external factors studied in this experiment.
June, 1952] D. P. MUKHERJEE AND P.BHATTACHARYA 87
pH of semen
The hydrogenion-concentration has been recognised by several investigators
as one of the many characteristics of semen for evaluation of its quality. From
analysis of data for individual bull, pH of semen did not seem to have any special
significance except that it indicated in a general way other qualities such as, sperm
concentration, initial motility and total number of spermatozoa. The pH value
of semen was usually found to lie between 6.22 to 6.34. Higher pH value was
associated with low values of other semen characteristics and vice versa.
During the latter part of the experimental period, the pH value in one bull,
however, was found not to lie within the range but was 6.8 or above. As mentioned
earlier this was due to an infection in its seminal vesicles. Anderson [1945,a] also
observed that in conditions involving pathology of genital organs the reaction of
semen was characteristically alkaline.
Results obtained in this experiment on the effect of season on pH are in agree-
ment with those reported by Erb et al. [1942], but not with those obtained by
Swanson and Herman [1944], Anderson [1945,b] and Raps and Cannon [1947]. It
may be mentioned here, that there existed a highly significant seasonal variation in
sperm concentration. As the sperm concentration of semen in individual bulls was
negatively correlated with the pH of semen, it was to be expected, therefore, that a
seasonal trend in pH should also exist. The results, however, did not show any
such trend. This might be due to the fact that pH was determined in this investiga-
tion with B. D. H. capillators by colorimetric method. Admittedly, the values
obtained with this method would be less accurate than what they would have been
if determined by glass electrode pH meter. But it appears that as pH is a general
indication of semen quality it failed to show any definite seasonal trend.
Initial motility
Initial motility as estimated by direct microscopical examination is dependent
upon the activity of spermatozoa as well as the sperm concentration. Variations
in sperm concentration will, therefore, reflect on the degree of initial motility.
Analysis of the present data showed highly significant variation among bulls and
between different years, and significant variation among seasons. The results,
on the whole agree with those reported by Erb et al. [1948], Sawnson and Herman
[1944], Salisbury [1944] and Anderson [1945,b] but differ from the findings of Phillips
et al. [1943] and Mercier and Salisbury [1946] who reported no significant seasonal
variation in the initial motility.
Sperm concentration
Determination of this characteristic is essential in order to appraise the fertiliz-
ing capacity of the semen sample. Result of analysis of data on sperm concentra-
tion showed that it was highly variable among bulls and among seasons. This
agrees with the results reported by previous workers except Anderson [1941] and
Swanson and Herman [1944].
4A