91

On referring to treatises on the diseases of animals
I find that cattle are in like manner subject to—

1. To uncomplicated inflammation of the lungs
   and their investing membrane, a sporadic
   non-specific disease, caused by exposure to
   weather, fatigue, surfeit, &c.

2. To the same disease, having for its cause a
   specific poison emanating from other animals,
   and having a tendency to spread as an epi-
   zootic over extensive districts.

But while in typhus, fever, erysipelas,
&c., the rash and other lesions for the
most part distinguish their intercurrent pneumonia
from the non-specific variety of the disease, the like
indications are not pointed out (in any treatises to
which I have access) as existing in the bovine diseases,
and therefore the diagnosis is more difficult.

Under these circumstances I am of opinion that in
the bovine pleuro-pneumonia, we must in all cases
rest our diagnosis on the previous history of the
cattle, whether exposed to specific contagion or not?
and that if the previous history be doubtful, the ex-
periment of exposing healthy animals to the con-
tagium generated by the reputed diseased animals,
would be, if fully carried out, an undoubted means of
discriminating between the sporadic and epizootic
diseases, and would, if the healthy animals become
contaminated, justify Government in at once enforc-
ing a rigid quarantine.

One experiment of this kind has already been tried-
the bovine pleuro-pneumonia, we must in all cases
Queensland, were confined for some days in the hold
of a ship coming from that place to Nelson, under the
most favorable conditions for the development of the
contagium of pleuro-pneumonia, if germs of the
disease were present: under similar circumstances in
the case of human beings, had the contagium of
typhus been present, a vast large number would
have sickened and died; in this case, as only a few
animals died during or after the voyage, there is a
strong prima facie case for assuming the non-specific
nature of the disease from which they did die, more
particularly as at this season animals are sent sud-
denly from a warm confined atmosphere to the open
pasture are likely to contract sporadic pneumonia.

Another experiment on a smaller scale has been
tried with opposite results. A few of the reputed
infected beasts were placed on a farm with a few
others previously healthy, and one or two of the
latter were soon after attacked with inflammation of
the lungs and died. This experiment was on so
small a scale that, though it is suggestive of caution
and further inquiry, it is, in my opinion, inconclusive
regards establishing whether the disease from which
they died was simple sporadic pneumonia, or had its
origin in contagium generated by previously diseased
animals.

From these two experiments it seems probable
that the epizootic (if it be such, which as yet I
doubt) is produced by a contagium of but little
diffusive energy, resembling that of enteric
fever, in being propagated by water contaminated
by the discharges of similarly diseased individuals,
and therefore having no great disposition to spread;
rather than that of typhus, which may be diffused
through the air or carried by fomites for re-diffusion;
and that if proper precautions are taken it will be
safe and expedient, instead of destroying suspected
animals, to remove them in a wagon (to be used only
for that purpose) to some convenient place, where
they can be observed, and a few healthy animals
enclosed with them as a test of the communicability
of the disease.

I have no opinion to offer on inoculation as a test.
The period of inoculation, the part of the body
from which the contagium is to be taken when
mature, and the result—whether a like specific disease
or only a non-specific one, similar to the necessary
diffuse inflammation in man caused by accidental
inoculation of certain postmortal fluids during dis-
sections—being, so far as I am informed, undecided
points among most authoritative veterinarians.

Pending any further information it is desirable
that some definition of the leading symptoms of
pleuro-pneumonia should be placed before the public.
In the Veterinary Committee of the
Royal Agricultural Society of England published a
circular for general information, descriptive of the
several "Epidemic Affections to which Cattle are
Subject," from which I take the following defi-
nition:—

"Pleuro-pneumonia, or Lung Disease."

"The attack is mostly insidious, the animal ap-
pearing at the outset to be but little affected; the
eyes retain their brightness often to the termination
of the illness, the appetite is generally diminished,
but rarely lost, excepting in the advanced stage of
the disease. A short dry husky cough is one of the
earliest symptoms, it continues throughout, and is
easily excited by moving the animal, especially if
such movement is sudden. There is rarely any dis-
charge from either the eyes or nostrils, the breathing
is greatly increased and becomes painful as the disease
advances, a dull sound is emitted on gently percus-
sing the side of the chest over the diseased lung.
Firm pressure applied to this part will also cause the
animal to shrink. There is little or no alteration in
the fecal evacuations, excepting in the last stages of
the malady, when a diarrhea comes on. The warmth
of the body and the extremities is often retained to
the last hours of the illness. In milch cows the
quantity of milk is lessened, but the animal will fre-
quently yield a fair amount to the very last. The
infected animal will sometimes live for weeks."

In the preceding observations I have endeavored
to enunciate these broad and general principles,
everyone conversant with analagous human
epidemics is competent to do, but I have expressed
myself with reserve and caution on some minor
matters of detail, with which, not having access to
any very authoritative veterinary treatises, I have bal
no means of acquainting myself. In the following
remarks I shall express my opinion without reserve,
the question being one on which, as a medical man,
I am able to offer an authoritative statement:-

During the last year many cases of indigestion,
diarrhea, and other forms of impaired health, have
come under my observation, which persons who took
but a cursory view of them, in the absence of any
more apparent cause, were disposed to attribute to
atmospheric influences. Being myself of opinion that
no such influences exist in our eminently healthy
climate, I felt it necessary to seek for some other ex-
planation, and in doing so have come to the deliberate
conviction that some disease, as well as de-
ficiency of bodily and mental vigor, which I have of
late had to treat, was caused by the very un-
wholesome bread and meat which every one has more
or less been compelled to use for some time back.
Excepting to make due allowance for it, as one of the
causes in operation, it would be foreign to the scope

• Published by authority of the Veterinary Com-
  mittee of the Royal Agricultural Society of England,
  in The Veterinarian, page 633, October 1865.