The author acknowledges himself indebted for what follows under this
head to R. McClure, V. S., of Philadelphia, author of a Prize Essay on
Diseases of Sheep, read before the U. S. Agricultural Society, in 1860,
for which a medal and diploma were awarded.
Although the small-pox in domestic animals has, fortunately, been as yet
confined to the European Continent--where it has been chiefly limited to
England--no good reason can ever be assigned why it should not at some
future time make its appearance among us, especially when we remember
how long a period elapsed, during which we escaped the cattle plague,
although the Continent had long been suffering from it.
The small-pox in sheep--_variola overia_--is, at times, epizooetic in the
flocks of France and Italy, but was unknown in England until 1847, when
it was communicated to a flock at Datchett and another at Pinnier by
some Merinos from Spain. It soon found its way into Hampshire and
Norfolk, but was shortly afterward supposed to be eradicated. In 1862,
however, it suddenly reappeared in a severe form among the flocks of
Wiltshire; for which reappearance neither any traceable infection nor
contagion could be assigned. With the present light upon the subject, it
would seem to be an instance of the origination _anew_ of a malignant
type of varioloid disease. Such an origin is, in fact, assigned to this
disease in Africa, it being well established that certain devitalizing
atmospheric influences produce skin diseases, and facilitate the
appearance of pustular eruptions.
The disease once rooted soon becomes epizooetic, and causes a greater
mortality than any other malady affecting this animal. Out of a flock
numbering 1720, 920 were attacked in a natural way, of which 50 per
cent. died. Of 800 inoculated cases, but 36 per cent. died.
Numerous experiments have proved beyond all doubt that this disease in
sheep is both infectious and contagious; its period of incubation varies
from seven to fourteen days. The mortality is never less than 25 per
cent., and not unfrequently whole flocks have been swept away, death
taking place in the early stages of the eruption, or in the stages of
suppuration and ulceration.
The _symptoms_ may be mapped out as follows: The animal is seized with a
shivering fit, succeeded by a dull stupidity, which remains until death
or recovery results; on the second or third day, pimples are seen on the
thighs and arm-pits, accompanied with extreme redness of the eyes,
complete loss of appetite, etc., etc. It is needless to enumerate other
symptoms which exist in common with those of other disorders.
_Prevention._ At present, but two modes are resorted to, for the purpose
of preventing the spread of the disease, which promise any degree of
certainty of success. The first is by _inoculation_, which was
recommended by Professor Simonds, of London. This distinguished
pathologist appears to have overlooked the fact that he was thereby only
enlarging the sphere of mischief, by imparting the disease to animals
that, in all probability, would otherwise have escaped it. By
inoculation, moreover, a form of the disease is given, not of a modified
character, but with all the virulence of the original affection which is
to be arrested, and equally as potent for further destruction of others.
By such teaching, inoculation and vaccination would be made one and the
same thing, notwithstanding their dissimilarity. Even vaccination will
not protect the animal, as has been already shown by the experiments of
Hurbrel D'Arboval.
The second and best plan of prevention is _isolation and destruction_,
as recommended by Professor Gamgee, of the Edinburgh Veterinary College.
This proved a great protection to the sheep-farmers of Wiltshire, in
1862. In all epizooetic diseases, individual cases occur, which, when
pointed out and recognized as soon as the fever sets in and the early
eruptions appear, should be slaughtered at once and buried, and the rest
of the flock isolated. By this means the disease has been confined to
but two or three in a large flock.
_Treatment._ In treating this disease, resort has of late been had to a
plant, known as _Sarracenia purpura_--Indian cup, or pitcher
plant--used for this purpose by the Micmacs, a tribe of Indians in
British North America. This plant is indigenous, perennial, and is found
from the coast of Labrador to the shores of the Gulf of Mexico, growing
in great abundance on wet, marshy ground. The use of this plant is
becoming quite general, and good results have almost uniformly attended
it.
Take from one to two ounces of the dried root, and slice in thin pieces;
place in an earthen pot; add a quart of cold water, and allow the liquid
to simmer gently over a steady fire for two or three hours, so as to
lose one-fourth of the quantity. Give of this decoction three
wine-glassfuls at once, and the same quantity from four to six hours
afterwards, when a cure will generally be affected. Weaker and smaller
doses are certain preventives of the disease. The public are indebted to
Dr. Morris, physician to the Halifax (Nova Scotia) Dispensary, for the
manner of preparing this eminently useful article.