22
THE EFFECT OF FEEDING THYROPROTEIN ON SEMEN (III) [Vol. XXIII, Part I,
factors were held constant. The values of R for control and experimental groups
are 0.206 and 0.361, respectively. These values are non-significant.
DISCUSSION
The increase in pulse rate, rate of respiration and body temperature of the
experimental group indicated that by feeding thyroprotein to the animals their
basal metabolism increased. The conspicuous decrease in the body weight of the
treated animals clearly indicates that the administration of thyroprotein at the rate
of one gram daily (this is the dose recommended by the manufacturer) continuously
over a long period proved excessive. The effect of an over-dose was shown by
majority of the animals after 8 or 9 weeks of thyroprotein feeding by their lethargic
movements and dull coat colour.
To study the reactions of the two groups to the variable atmospheric conditions
under which the experiment was conducted, the data on pulse rate, rate of respiration
and body temperature of the animals and atmospheric factors were statistically
analysed. From the partial correlation coefficients in the control group, it is apparent
that humidity played a significant part in the fluctuations of the pulse and respiration
rates. Increase in humidity decreased the pulse and respiration rates and vice versa,
when air temperature and rainfall were held constant. Sheath and Miller [1946]
found that in dairy animals, changes in air temperature or relative humidity had
little effect on the pulse rate. They further observed that relative humidity played
a minor role and air temperature a major role in the variation of respiration rate.
Sheath and Miller recorded an average relative humidity of 56.8 per cent during their
study, whereas in this experiment the average humidity was observed to be 72.8
per cent (Table II). It may be possible that a low relative humidity of 56.8 per cent
has little effect on the rate of respiration and pulse rate.
During the variations in air temperature, humidity and rainfall, it was found,
as already stated, that fluctuations in air temperature played a major role in the
variation of pulse rate. Under similarly variable atmospheric conditions the varia-
tions in the rate of respiration were mainly due to changes in humidity. Importance
of the variations in pulse and respiration rates may be explained as follows:
Homeothermic animals, like goats, maintain their normal body temperature with
the help of thermo-regulative devices. One of the major physical mechanisms in
such animals for dissipating their extra body temperature is by the acceleration of
their respiratory mechanisms.
In this experiment it was found that when the humidity increased the air tempe-
rature decreased (partial correlation coefficient being —0.792). Increase in humidity
also decreased the pulse and respiration rates of the animals (the partial correlation
coefficient being —0.713 and —0.671 respectively). In the reverse order, when
humidity decreased, air temperature increased and there was a concomitant increase
in the pulse and respiration rates. As the statistical analysis showed that the body
temperature was uninfluenced by the changes in atmospheric factors, it seems that
changes in pulse rate and rate of respiration of the animals were so perfectly adjusted
to the changes in atmospheric factors that the animals could maintain their normal
body temperature in spite of changes in atmospheric conditions.