SCOTTISH METROPOLITAN VETERINARY ASSOCIATION. 8 77 
when domesticated) as fat almost as it was possible to make 
them, kept for breeding purposes, without one of their number 
being the subject of parturient apoplexy (and they always pro¬ 
duce small calves) ; the reason is obvious: they are allowed 
plenty of exercise both prior and subsequent to calving, and the 
calves are left with them to suck at will. I am told also that 
amongst the Chillingham herd attacks of this kind are rarely, if 
ever, observed. In those cases which arise about the second or 
third day after parturition it is not improbable that the detach¬ 
ment of small thrombi in the veins of the womb, and their 
lodgment in the capillary vessels of the brain and spinal cord 
may act as a centric cause; this is rendered more probable from 
the fact that in these post-partum cases the attack is frequently 
ushered in with rigors. 
I must not pass from this point of my subject without making 
some remarks as to the reasons why this disease seldom follows 
abortion, or difficult parturition. In abortion, with few excep¬ 
tions, there is a gradual severance of the materno-foetal circula¬ 
tion ; no §udden shock exerts its baneful influence upon the 
system, and very frequently it occurs in the earlier periods of 
utero-gestation when comparatively little blood circulates the foetal 
membranes and blood-vessels. 
In difficult parturition, occurring in fat animals or those in 
high condition, a large percentage of the nitrogenized consti¬ 
tuents existing in the blood is u^ed up by the active exertions to 
get rid of the foetus, thus rendering the blood less plastic in its 
character ; moreover, from the prolonged period of parturition 
the circulation returns to its normal condition more gradually, 
and excitement is kept up for some time; difficult parturition 
does not so often occur in fat as in lean animals, for the reason 
that the calves of the former are generally smaller than those of 
the latter, and being more docile they are not so much exposed to 
the usual causes of cross-births. 
The pathology of the disease .—I have already referred to the 
fact that in many instances the sympathetic system of nerves is 
primarily involved, I must now proceed to show you how and 
why this is the case :— 
Irritation of the sympathetic nerve is followed by loss of func¬ 
tion ; the primary effect of the irritation would be exalted func¬ 
tion, which exaltation would indirectly act upon the circulatory 
system producing the staring eye, injected conjunctiva, and 
quickened pulse; the irritation being kept up loss of function 
follows. Division of the cervical sympathetics is followed by 
paralysis of the blood-vessels of the brain; the fibres supplying 
the blood-vessels of the head arising from last cervical and first 
dorsal (Brown-Sequard). Pressure on any important branch, or on 
