DISEASES OF SHEEP.
(119.) There is no department in the management of sheep so little
understood as the nature and treatment of their diseases. Every part of
the sheep itself has been used, at one time or another, in this
country, as medicine for _man_, a folly still prevailing among the
boors of Southern Africa, who, according to Thunberg, employ the inner
coat of the stomach, dried and powdered, as a safe emetic. Quackish
absurdities of so glaring a nature have, however, long been scorned in
civilized society. Not so, however, when the sheep is the object of
treatment. Scientific innovations have been slow in reaching it, and
specimens of barbarian usage are far from rare. We may feel for the
benighted credulity which could place reliance, for a rescue from
mortal ailment, on the secretions or excretions of a sheep; but we are
compelled to laugh on reading, in the _Family Dictionary_, published in
1752, the following:--
"In general, 'tis affirmed that the belly of a sheep boiled in water
and wine, and given the sheep to drink, cures several diseases incident
to them."
Only fancy a farmer dosing a sheep with mutton broth, and adding, for
its stomach's sake, a little wine! I suspect the prescriber was, in
this instance, putting himself, in point of intellect, far below the
level of his patient. Thanks to him, however, for the benefit he has
thus unwittingly conferred, by holding ignorance up to the derision it
so richly merits; no means being so powerful as broadly-drawn
caricatures in exposing the extent of such delusions. Though faith has
long since ceased to be reposed in the medicinal virtues of mutton
broth, a variety of nostrums have from time to time appeared, the
composition and application of which are invaluable for the amount of
_negative_ information they are calculated to convey. Further notice of
these trashy recipes it is not my intention to take, as a list of them
alone would make a volume;--they are in the hands of every one.
(120.) _Cautions in prescribing._ Great reliance is in general placed
upon prescriptions, which profess to suit diseases in every stage and
circumstance.--Than this, however, scarcely any thing can be more
absurd. It is an opinion engendered not so much by ignorance as by
laziness, a determination not to be put about by thinking of a remedy
for the evils which surround us, but, while we contrive to soothe
ourselves by doing _something_, to leave every thing to the hit-or-miss
practice of charlatans.[24] There are many, who on being informed of
the presence of disease in a neighbour's flock, confidently advise the
employment of a favourite nostrum, on the empirical supposition that
because it cured, or was thought to cure, one flock, it will cure
another. Nothing is taken into account saving that, in both cases, the
affected animals are sheep; and it is at once concluded, that what
benefited one will benefit another. The many niceties in prescribing
are never thought of: oh no, that would be of no use! of course it can
be of no importance to give a moment's attention to age and sex,
pasture and situation, or to leanness or fatness, or to the presence of
pregnancy! These are of trifling moment, and only to be despised by a
person armed with a recipe, which some one has shown to be capable of
walking like a constable through the body, and bearing off the
intruder! But enough of this; sufficient has, I think, been said to
prove the utter folly of confiding in things of the above nature or
intention, and to show that such confidence can lead to nothing but a
waste of life and capital. Even though the remedy is a harmless one, it
ought (unless calculated from _known_ powers to arrest the disease) to
be viewed with distrust, as incurring a loss of time, during which
other and better measures might have been resorted to.
[24] Whenever we hear a person recommending a medicine of
universal virtues, we may safely set him down either for a fool
or an impostor. Things which are good for every thing are good
for nothing.
(121.) _Classification of diseases._[25] As the acquirement of correct
ideas regarding the treatment of diseases is much facilitated by a
simple arrangement of the diseases themselves, numerous attempts have
been made to accomplish it, and in a variety of ways. The best of these
tabular views with which I am acquainted is the one laid before the
Highland Society some years ago, by Mr Stevenson, who appears to have
been the first to publish any thing like a satisfactory classification.
His arrangement is, however, defective in several points, more
especially as it necessitates the placing in the same division diseases
of organs essentially different. Thus he is compelled to admit under
"Diseases of the head" _Scabs on the mouth_ side by side with _Sturdy_,
and _Louping ill_: in this way mingling affections of the skin with
diseases of totally different organs--the brain and spinal marrow--and
causing much embarassment to the reader. To obviate this inconvenience,
as well as to render the remembrance of the remedies an easy matter, I
have adopted the above arrangement, in which each disease is placed
opposite the textures it invades.
[25]
Diseases affecting
{Blown or Blast.
{Braxy, Sickness, or Blood.
The Stomach and {Pining, Daising, Vinquish or Vanquish.
Intestines. {Staggers.
{Diarrhoea or Rush.
{Dysentery, Cling, Breckshaw or
{ Breckshuach.
{Scab or Itch.
{Erysipelas or Wild-fire.
{Red Water.
{Leg Evil or Black-leg.[26]
The Skin and {Inflammatory {1. Maggot.
Hoofs. { appearances {2. Ked.
{ caused by the {3. Tick.
{ {4. OEstrus bovis.
{Sore Teats.
{Foot-rot.
{Inflammation {1. OEstrus ovis.
The Air Passages. { caused {2. Pentastoma.
{ by the {3. Strongylus filaria.
{Coryza.
Glandular tissues,{Rot.
--viz. the Lungs, {Jaundice.
Liver, & Kidney. {Dropsy.
{Sturdy, {1. Hydatids or Bloba.
{ Gid or Dizzy, {2. Hydrocephalus, or
The Brain and { caused by { Water in the Head.
Spinal Marrow. {Trembling, Thwarter or Leaping-ill.
{Wood Evil.
The Eye. {Ophthalmia.
{Soft Cancer.
[26] Leg evil ought properly to be classed with diseases of the
vascular system, being in many instances merely a symptom of
disease in the heart or great vessels; but as the same results
are arrived at by placing it under the present head, nicer
distinctions would only tend to create confusion.
(122.) _Blown or Blast._ Can scarcely be reckoned a disease as it is
but a symptom caused by a mechanical impediment to respiration and
circulation. When a sheep has been brought from a poor pasture to a
rich one it is prone to gorge itself to an extent which may endanger
life. The lower end of the gullet becomes obstructed, the gases which
accumulate in the paunch are hindered from escaping, and the latter
becomes so enormously distended as speedily to suffocate the animal by
being forced into the chest.
(123.) _Treatment[27] of Blown._ If the difficulty in breathing be only
slight, keep the sheep moving _gently_ up and down as the air will thus
have a chance of escaping from the stomach. If the symptoms are more
alarming, pass the elastic tube employed in the same complaint in
cattle down the throat, or if that cannot be procured use a cane with
an ivory or wooden bullet at the end of it. Never _stick_ the animal,
as recovery by this plan is almost hopeless. If you cannot obtain the
aforesaid instruments, bleed the animal till it becomes very faint, and
if this is of no avail proceed to kill it. Shepherds often prescribe a
purgative dose after this occurrence. In general, however, it is not
required. To prevent a flock becoming _blown_, always when, for the
first time on rich pasture, make the dog move leisurely among them so
as to prevent them feeding hastily.
[27] In speaking of remedial measures, the word treatment ought
to be used in preference to "_cure_" which figures at the head
of the medical advice in veterinary works. It is sheer nonsense
to blazon such a word in pages having any pretentions to
candour, for how seldom are we able conscientiously to affirm
that our endeavours will be followed by a _cure_. All we can do
is to pursue the _treatment_ best adapted for the attainment of
so desirable an end.
(124.) _Braxy or Sickness._ Six or eight species of braxy are
enumerated by shepherds, but as they all bear a striking resemblance
one to another, in their origin and progress, it is preferable to treat
of them as one disease. Indeed wire-drawn distinctions, though
occasionally serviceable in cattle-medicine, ought in most instances to
be avoided, as they are of but little avail, and in this disease
straw-splitting can only serve to tantalize the farmer, by giving rise
to ideas of finical modes of treatment, which before the Chapter ends
are reduced to the simplest aids which medicine affords. Whatever may
be the seat or seats of the disease, the identically same resources are
employed in all:--why therefore ought the reader to be troubled with a
hundred trifling phases, which, not being _essential_ to the malady,
can only tend to perplex him in his search for the little that is
practically available.
(125.) _Symptoms of Braxy._ In those rare cases where the animal is
seen at the commencement of the disease, it will appear uneasy, lying
down and rising up repeatedly, loathing food, and drinking frequently.
In a little while the symptoms become more decided, and fever shows
itself. The wool is clapped, the skin hot, the pulse quick and strong,
respiration is rapid and laborious, while the blood is thick and black,
issuing from the orifice, in attempts at bleeding, drop by drop.
Sometimes the heart beats irregularly: the mouth is parched, and the
eyes are red, languid, partly closed, and watery. The head is down, the
back drawn up, and the belly swollen; there is scarcely any passage
through the bowels, the urine is small in quantity, high coloured, and
sometimes bloody. The sheep shuns the flock, slowly dragging itself to
some retired spot, where convulsed and screaming it shortly dies. Death
may occur in a few hours, or may, in some rare cases, be delayed for a
week. A fatal termination is not so sudden as some have fancied, since
the animal is in general seriously ill for many hours before it is
discovered.
(126.) _Appearances on dissection._ Though many parts are commonly
implicated in the _sickness_, there is every reason for believing the
_reed_ to be primarily affected. Inflammatory appearances, and
mortification, the usual result of violent inflammation in this
quarter, are visible on its coats, especially at the pyloric extremity
(Plate I. Fig. 2, _py_.) The inner coat presents a blackish-red, and
gelatinous appearance,--the entire bowel being soft, pulpy, and easily
permeable to the finger. The intestines, kidneys, and bladder, will, in
all probability, exhibit similar changes, while the lining membrane of
the abdomen (the _peritoneum_) is frequently affected: when this
membrane has been much inflamed, the intestines are glued together, are
surrounded with bloody or floculent serum, occasioning before death
tumidity of the under part of the belly, and communicating, when
struck, a feeling of fluctuation to a hand placed at a distance from
the blow. The muscles in various parts of the body frequently
participate in the disease, bloody serum being infiltrated between the
layers. As the brain, in severe cases, exhibits symptoms of oppression,
so on dissection it will be found red and turgid, enabling us to
account for the convulsive movements during the termination of the
malady. The whole body, more particularly the abdomen, gives out a
fetid gangrenous odour, which has procured for braxy the pastoral
appellation of "_stinking ill_" and renders the dissection far from
pleasant. After death putrefaction goes on with great rapidity,
especially in moist weather, hence the necessity of testing the
solidity of the carcass by giving it, as is customary in some parts,
_three shakes_ before proceeding to prepare it for household use!
(128.) _Causes of Braxy._ Whatever tends to constipate the bowels may
be reckoned a predisposing cause. Whenever constipation occurs,
especially if on a sickrife pasture, the sheep may be looked upon as
ripe for the disease. Any crude indigestible substance, taken into the
stomach when the animal is in this state, will have a tendency to
kindle braxy, and the liability to it will not only be heightened, but
the chances of recovery will also be lessened, by the animal being in
high condition.
Wedder hogs are peculiarly its victims, but only when hirsled, as when
allowed to pasture with their mothers they are less liable to it. This
is accounted for by the fact, that hirsled hogs are comparatively
_dull_, not being familiar with the proper times for feeding, and
incapable of selecting the suitable herbage, from having wanted the
tutoring of the mother.
From the beginning of November till the middle of March, _sickness_
commits its greatest ravages, especially among heath sheep, from their
being more confined than others to dry binding provender. Frozen grass
is also a common exciting cause, rapidly inducing inflammation by
lowering the temperature of the stomachs so very much as to arrest
digestion, and lead to its acting as an irritant. The succulent grass
in the sheltered hollows of mountains is more liable to frost than a
sapless herbage, and to it, owing to its moisture, the young sheep
resort, devouring it eagerly to assuage their thirst. Braxy, however,
may arise from other and more obvious causes. The sheep, perhaps when
heated by rash dogging, is suddenly chilled by exposure to a shower, or
a plunge in a morass, and if the bowels be at the time any way bound
up, immediate mischief cannot but ensue. One of the rarest accidents to
which it has been attributed is the prevention of the passage of the
faeces by a knot, or intussusception, forming on the intestines, but
this occurrence would be of difficult discovery, and even if made
known, our treatment, though not differing much from that of braxy,
could hardly be successful.
(128.) _Treatment of Braxy._ Recovery is in many instances almost
hopeless, owing to the length of time which in general elapses between
the onset of the disease and the shepherd's discovery of the animal.
Nevertheless, the best treatment ought in every instance to have a
proper trial, as life may often be saved when such a result is least
expected. Many plans have been resorted to, but none are found to suit
so well as that of bleeding and purging. The first thing to be
attempted is the procuring of a copious flow of blood, but, as before
mentioned, this is a difficult matter, owing to the stagnant state of
the circulation at the surface of the body. Its abstraction may,
however, be rendered easy, by placing the sheep in a tub of warm water,
or, where this cannot be procured, by rolling a blanket wrung out of
hot water round the body of the animal. The tub of water should always
be preferred, and the moment the sheep is placed in it, the tail should
be nicked, and one or both jugular veins opened.
Retain the sheep in the bath for half an hour, adding hot water from
time to time, so as to sustain the original temperature. This of itself
will alleviate the sufferings of the animal.
When a copious flow of blood has been obtained, remove the sheep from
the tub, and administer two ounces of Glauber's or Epsom salt,
dissolved in warm water, substituting a handful of common salt when
these cathartics cannot be procured. It is needless to give a purgative
without bleeding, as, till this is done, it will not operate. When in
spite of this the bowels continue obstinately constipated, give a
glyster of tobacco decoction, made by boiling a drachm of the leaf (the
full of a pipe will do) for a few minutes in a pint of water. Half of
this only should be injected, using the other if circumstances require
it. Place the sheep in a house, or any comfortable situation, bed it
with straw, throw a horse-rug over it, and promote the purging by warm
gruels. When out of danger supply it with moderate quantities of
laxative provender, and keep it for ten days apart from its fellows, by
which time it will, in all likelihood, be well recruited.
(129.) _Prevention of Braxy._ Change of pasture will at once suggest
itself. Let it be to a succulent one, on which old sheep have been for
some time feeding; the hogs will thus be hindered from filling their
paunches too rapidly. But, if heathy food is the staple provender,
allow your sheep four or five hours of turnips in the twenty-four,
permitting at the same time free access to common salt. These, from
their laxative effects, will serve as antidotes to the dry sapless
grasses, which have led to the disease. Such places as mossy soils,
abounding in evergreen plants, will also serve the purpose. Burn your
ley heather, as nothing is more decidedly prejudicial, not only from
its constipating qualities, but also from being surrounded by a grass,
which is so much relished by the sheep, that they resort to the spot
long after it has been eaten to the quick, and devour in their
eagerness much that is foul and unwholesome from frequent puddling. You
thus obtain a good supply of sprouts, as invaluable for opening
qualities, as the old heather is to be dreaded for its astringency.
Finally, be aware that careful herding is not the least efficacious of
preventives; a quiet, even-tempered, and thoughtful shepherd, being
here of far more value than the stores of the apothecary.
(130.) _Pining._ _Symptoms and Causes._ The name has arisen from the
rapid wasting, which is a prominent symptom in this complaint. A farm
can hardly be subject to a more ruinous distemper, as the same sheep
will be affected by it year after year, and if a ewe be attacked during
autumn it is ten to one she will not have a lamb in the ensuing season.
Pining only seizes on thriving sheep, preferring young ones, those more
especially of the larger breeds, and is confined to farms where the
land is principally micaceous and covered with occasional stripes of
benty grasses. A whole flock sickens at once, their usual alacrity
appears to have deserted them, their eyes are dull, and the whole
animal seems weary and languid. At a more advanced stage the wool
acquires a bluish tinge, the blood becomes thick, diminishing in
quantity, and the muscles assume a pale and bloodless appearance. The
bowels are constipated, and to this the feverish symptoms apparently
owe their origin. If the disease progress, death will ensue in about a
month.[28]
[28] A gradual wasting of the animal, similar to what occurs in
pining, may result from the irritation consequent on swallowing
pointed bodies, as pins or needles. I have in my possession a
very stout needle, given me by Mr Wilkin of Tinwald Downs,
which was found buried in the coats of the stomach of a young
sheep which died under the above symptoms, having been ill
about three months.
(131.) _Treatment and Prevention._ The first object is to obtain a free
discharge from the bowels by means of purgatives, as, whenever a flux
appears, the animal is safe. Two ounces of Castor oil given in a gruel,
or the same quantity of Epsom salts, will do, care being taken that the
purging be carried to some length.
Removal to a rich pasture is the only preventive. That pasture should
be preferred which contains a good proportion of bitter plants, for the
emaciation appears to be owing in a considerable degree to torpor of
the bowels occasioned by long abstinence from these necessaries.
(132.) _Staggers._ The symptoms nearly resemble those of sturdy, which
I have afterwards to describe, and with which indeed I might have
classed it, were it not that it appears to be merely the result of a
poisonous plant being taken into the stomach. It is rarely seen
hereabouts; I shall, therefore, quote the account of it presented to
the Highland Society by Mr Stevenson:--"This is a disease seldom or
never affecting the sheep in this country, those excepted which feed in
forests, or amongst planting. The symptoms of it are more violent than
those of sturdy, during the time of their continuance. The animal,
after staggering for some time, falls on the ground, when a general
trembling comes on over the limbs; they are violently convulsed, and
quite insensible to every thing. During the continuance of the paroxysm
they throw the body into various positions, and sometimes roll to a
considerable distance. The fit continues for a quarter, sometimes half
an hour, or an hour. When they rise, they seem perfectly bewildered,
till they regain the flock, when they continue to feed well, till
another paroxysm supervenes. This disease appears in Autumn, and
various causes are said to produce it. Improper food, the leaves of the
oak, from their astringent quality, cobwebs sprinkled with dew, have
all been reckoned as causes. I am inclined, however, to suppose, that
it arises from the action of a poisonous grass (_Lolium temulentum_),
which is the only one of that description in this country, and grows
only in those situations where staggers prevail. What effect these
causes have on the brain to produce this disease, I cannot explain.
When it continues for any time on the same individual, it is apt to be
fatal."
"Change of pasture is the only effectual cure for it."
(133.) _Diarrhoea._ By this is meant a constant purging, affecting the
younger portions of the flock between April and June, leading to great
emaciation, and proceeding from one of the following causes.
1st. Eating a soft tathy pasture, particularly if fouled by the
inundations of the previous winter.
2d. Feeding on too rich a pasture, or a sudden change from an
herbage deficient in nutritive qualities, to one that is much
superior.
3d. Transitions from heat to cold.
4th. Weakness and relaxation of the bowels.
(134.) _Treatment of Diarrhoea._ When either of the first two causes
has given rise to purging, a moderate allowance of good hay will
gradually stop it. This may be discontinued when the sheep has _taken_
with its altered fare.
When diarrhoea has been occasioned by exposure to damp, or sudden
transitions from heat to cold, it may be arrested by keeping the animal
in a house for a few days, and feeding it on any dry aliment, but when
crude trashy matter has been swallowed, and keeps up irritation by its
presence, medicine must be resorted to. Administer an ounce of castor
oil in gruel, adding twenty drops of Laudanum if there has been
straining or evidences of pain. When the bowels have been _thoroughly
cleared_ by this cathartic, it will be proper, if the discharge still
continue, to check it by astringents. The medicine found by experience
to answer best, is prepared as follows:--
Take of Logwood four ounces,
Extract of Catechu (Japan earth) one drachm,
Cinnamon two drachms,
Water three English pints.
Boil for a quarter of an hour, strain, and then add sixty drops of
Laudanum. Administer half an English pint of this night and morning so
long as the flux continues.
Diarrhoea seldom proves fatal, and is indeed an easily managed disease;
but as it is frequently only a symptom of some other affection, or a
critical effort of the constitution to ward off some more serious
mischief, the attempts at stopping it should always be cautiously
conducted.
(135.) _Dysentery.--Symptoms._ The pulse is quick and the respirations
hurried. The skin is harsh and hot, and the wool in general clapped.
The mouth is dry, the eyes red and languid, and the ears drooping. Food
is taken only in small quantities and rumination is stopped. The
discharges from the bowels are frequent, slimy, sometimes green, and a
little further on in the disease are mixed with blood. The belly is
drawn towards the back. It is knotted and lumpy to the touch and a
rumbling noise (_borborygmus_) is heard within it. As a careless
observer might have some difficulty in distinguishing dysentery from
diarrhoea the following diagnostic summary, drawn up by Professor
Duncan, will be found of service.
1. Diarrhoea attacks chiefly hogs and weak gimmers and dinmonts;
whereas dysentery is frequent among older sheep.
2. Diarrhoea almost always occurs in the spring, and ceases about
June, when dysentery only commences.
3. In diarrhoea there is no fever or tenesmus, or pain before the
stools, as in dysentery.
4. In diarrhoea the faeces are loose, but in other respects natural,
without any blood or slime; whereas in dysentery, the faeces
consists of hard lumps passed occasionally without any blood or
slime.
5. There is not that degree of foetor in the faeces in diarrhoea
which takes place in dysentery.
6. In dysentery, the appetite is totally gone, in diarrhoea it is
rather sharper than usual.
7. In dysentery, the animal wastes rapidly, but by diarrhoea only a
temporary stop is put to its thriving, after which it makes rapid
advances to strength, vigour and proportion.
If dysentery continue to advance it will terminate fatally within a
fortnight. Death is generally preceded by the "_black scour_," which is
only an aggravation of the purging, the stools being mixed with shreds
of dark gangrenous matter from the decomposed interior of the
intestines.
(136.) _Causes of Dysentery._ Many absurd opinions have gone abroad
regarding the contagious nature of this affection. Contagion, however,
has nothing to do with the matter, the spread of the disease depending
entirely on the state of the atmosphere and the nature of the locality.
When dysentery occurs the weather is usually sultry, the ground upon
which the flock has been going, foul, and the management of the sheep
so improper, as to be sufficient of itself to produce the disease very
generally. There is in fact only one proof of a disease being
infectious, viz., its immediate occurrence on the introduction of an
affected animal among such as are in good health, on sound food, and in
easy circumstances. This proof, however, in regard to dysentery has
never been established, and no medical person will now affirm that it
is contagious. Some think that it travels from flock to flock in the
direction of the wind, but its appearing simultaneously in many folds
ought rather to be charged to the fact of the predisposing causes being
nearly similar in all.
(137.) _Treatment of Dysentery._ Bleed freely if the disease has
continued only for a few days, but moderately if a longer time has
unfortunately elapsed. Stoving, by which is meant shutting the animal
in a wash-house, and allowing the apartment to become filled with
steam, though urged by some writers, cannot here be recommended. The
intended object is the promotion of perspiration, by exciting the
action of the skin, but this may be brought about by means much more
conducive to the safety of the animal. After the bleeding immerse the
sheep in a tub of hot water, and retain it there for twenty minutes;
then administer an ounce of Castor oil, with thirty drops of Laudanum,
and cover the sheep up in a snug corner. After the oil has operated,
thin well-boiled flour-porridge, given at intervals, in small
quantities, will help to defend the ulcerated bowels, sooth the pain,
and stop the purging. If these fail, you may use the astringent mixture
recommended in diarrhoea at page 175, and in the same manner, adding to
each dose a grain of ipecacuanha. When the appetite returns, and the
stools begin to acquire consistency, speedy recovery may be
prognosticated.
During recovery part of the wool always falls off.
(138.) _Prevention of Dysentery._ If you wish your sheep to take the
disease, do as some wiseacres recommend--put tar upon their tails, and
noses; you will thus render them feverish, and uncomfortable, and every
way fit for an attack.
Gathering sheep into confined places is always bad, nothing will tend
more to ward off dysentery than an open frequently-changed easy-lying
pasture, combined with gentle usage on the part of the shepherd.
DISEASES OF THE SKIN.
(139.) _Scab, or Itch._--_Symptoms and Causes._ These are so well known
that they hardly merit a description. Little white specks appear upon
the wool, and are soon followed by a small pustule at the root. The
pustules are produced by a minute insect burrowing in the skin, which
accounts for one external application of any active substance being
sufficient to eradicate the malady. The infected sheep is restless,
tearing off the wool with its teeth, and rubbing itself against every
resisting body. The skin is red and fretted, discharging an ichor which
hardens into crusts. These gradually extend, inducing a premature
failure of the wool.
If the sheep be not relieved, it sinks under its accumulated miseries.
Scab was little known any where, but in the Highlands, and the south of
England, till the good old custom of smearing with tar and butter gave
way before the elegant modern innovations. Into flocks anointed in the
old manner it may be carried by infection, but will seldom or never
arise spontaneously among them.
It usually commences in spring among hogs, making its first appearance
among the rams, especially those of the fine-woolled breeds, and is
supposed to be induced by overheating, want, or even excess of
nutriment, or pasturing on wet lands in rainy seasons.
(140.) _Treatment of Itch._ Subject the flock to a minute examination
whenever the movements of any animal excite suspicion, and remove every
one that is in the least affected. Place them in a separate enclosure,
and apply either of the following recipes.
Take of Mercurial Ointment four pounds,
Venice Turpentine half a pound,
Oil of Turpentine one pint:
mix thoroughly.
Separate the wool from the head to the tail and draw the fore finger
loaded with a portion of the ointment, along the bottom of the groove.
Then make lines from the middle of the back down each leg and score
them in the same manner, thus concluding the operation. Some farmers
prefer rubbing the size of a walnut of the ointment into the delicate
skin inside the thigh. The former plan is, however, the better of the
two, and is the one recommended by Sir Joseph Banks, who communicated
the recipe to the Society for the Encouragement of Arts, Manufactures,
and Commerce, in the 7th volume of whose transactions it was published.
A most important benefit to be derived from the application of the
mercurial ointment, is the security it affords the sheep from the
attack of the sheep fag or ked (_Hippobosca ovina_). The wool of sheep
annoyed by this fly always contains joints or knots, owing to the
occasional stoppage of its growth consequent on the fretting of the
irritated animal. On this account dealers in wool are said to give a
higher price for fleeces having the mercurial tinge, as they are
supposed to be sound in the pile from having been exempted from the
fly.
The next prescription is one of very great efficacy where the disease
has reached the length of scabs, and has, with many variations, gone
the round of almost every agricultural publication. The form I prefer
is one submitted to me by Mr Wilkin of Tinwald Downs, near Dumfries,
who at one time, several years ago, applied it with immediate good
effects, to six hundred infected sheep.
Take of Tobacco scrapings one pound,
Strong decoction of Broom six gallons:
boil for half an hour, and then add three English pints of spirit of
tar.
This quantity is sufficient to cover two dozen of sheep. The scabs, if
large, should be raised a little with a knife to permit the free
contact of the fluid, and no more of it should be applied than is here
directed; for though it be in this dose comparatively harmless, a very
small addition will destroy the animal.
A very good French remedy is made by melting a pound of fat or suet,
and mixing with it (when off the fire) a fourth part of oil of
turpentine. Rub it into the affected parts.
Whatever outward means may be employed, laxative medicines ought never
to be neglected. One of the best and most generally used, consists of a
tea-spoonful of flour of sulphur, given for two or three successive
nights in double the quantity of molasses.
If ill-conditioned sheep are the victims of itch, convey them to a
better pasture, but where the animals are fat, reduce their diet, and
give each a dose of Epsom salts.
(141.) _Prevention of Itch._ Do not turn a healthy flock on to pasture,
from which itchy sheep have recently been driven. If the disease
occasionally breaks out on your ground, apply the mercurial ointment at
clipping time: and, when you salve, add a pound of sulphur to every tub
of smearing composition whatever it may be.
(142.) _Erysipelas or wild-fire._ This is an inflammatory affection of
the skin, sometimes accompanied by blebs or blisters, occurring in
August and September, and spreading rapidly through a flock. Though
there is considerable ambiguity in the employment of these terms, I
believe they are synonymous with red-water, the disease of which I have
next to treat.
(143.) _Red-water._ The occurrence of this disease among sheep is very
rare. Its nature and treatment are however allowed, by those who have
seen it, to be admirably described by Mr Stevenson, in the 3d vol. of
the _Highland Society's Transactions_.
"This disease commonly makes its appearance about the beginning, or end
of winter, and first affects about the breast and belly, although at
times it spreads itself over other parts of the body. It consists in an
inflammation of the skin, that raises it into blisters which contain a
thin, reddish, and watery fluid. These continue for a short time,
break, discharge their matter, and are followed by a blackish scab.
When the sheep are exposed to cold or wetness, the skin being fretted
makes the blisters rise, or they often arise from cold, affecting the
animal internally, thus producing a slight fever, which throws out
these vesicles on the body, similar to the scabby eruptions, which
appear about the face, and more particularly the mouth of those persons
affected with cold. The blood in this disease is but little affected,
though a little of it oozes into the vesicles on the skin, and
communicates to them that reddish tinge, which gives origin to the
name.
"Red-water is a disease that but seldom appears in this country, and is
almost never fatal. In cases where the disease is violent, a little
blood should be taken. * * * * The sheep should be placed in a fold by
itself, * * * * and the following medicine may be given for three or
four mornings successively:--
Take of Flour of Sulphur two ounces,
Molasses three ounces:
mix them, and divide them into six doses, of which one may be given
every morning, in half a pound (half a mutchkin) of warm water. If this
is found unsuccessful, half an ounce of nitre, mixed with the foregoing
recipe, will be attended with good effects; after which, a dose of
salts may be given, and the body washed with lime-water upon the part
affected."
(144.) _Leg Evil._--_Symptoms and Causes._ Like many other diseases,
this is usually supposed to be contagious, merely because it often
spreads quickly through a flock; the obvious fact of the exposure of
the animals composing it to the same causes, such as peculiar diet and
atmospheric variations, being entirely overlooked; but, as I have
already remarked in paragraph (136), the only proof of a disease being
contagious, is its spreading rapidly on the introduction, from a
distance, of an infected individual into a previously-healthy flock.
Sheep which acquire fat at an early age, are peculiarly liable to this
disease: a sufficient argument, if all others were wanting, against the
unnatural and foolish practice of accumulating a load of grease on the
bodies of young animals. By so doing, the action of the heart and lungs
is materially embarrassed, and, on the animal being chilled, or the
balance of its circulation otherwise accidentally deranged,
mortification (leg evil) is almost certain to occur. Even simple
scratches are often fatal in these over-fat animals, from inducing
gangrene.
The first intimation the shepherd has of the approach of leg evil, is
the occurrence of fever and lameness, accompanied by blue or livid
patches on the leg, generally about the upper part of the hoof or knee.
The skin on the affected parts, in a few days, exhibits scattered
vesicles, not unlike the blebs which form in erysipelas; it then gives
way, and the parts beneath are seen of a darker tinge, soft, pulpy, and
completely gangrenous.
Leg evil may prove fatal in a few days, or not for several weeks, much
depending on the extent of the sloughing portions, which may include
the entire leg, or legs, or may be limited to a single patch.
(145.) _Treatment of Leg Evil._ When the animal is in high condition,
and the disease has arisen spontaneously, bleeding is the first thing
to be thought of. It must, however, be conducted cautiously, it being
better to use the lancet a second time, than, by withdrawing too much
blood, to reduce the vital powers below the standard which is necessary
for replacing the gangrenous portions. Should a leg be affected to any
extent, the sheep must be at once destroyed, as there is scarcely a
possibility of its surviving, without a degree of care and nicety in
the treatment, which it is beyond the power of unprofessional persons
to bestow. Where the livid spots are limited, rags dipped in spirit of
turpentine, which has been heated by immersing the bottle containing it
in hot water, may be laid upon the skin; but when dead portions have
begun to separate, the best application is either a warm poultice, made
of carrots, which have been boiled and mashed, or one made of boiled
oatmeal, which has been fermented by adding to it a table-spoonful of
yeast, and placing it for an hour before a fire. When the sore is
becoming clean, and the granulations are rising freely, pursue the
methods recommended in paragraph (110).
(146.) _Prevention of Leg Evil._ Remove the diseased animals from the
flock, and, in dressing their sores, never use a sponge, or any thing
which, from its value, is apt to be preserved, and, perhaps, applied in
no long time to the cuts or scratches of a healthy animal; for, though
leg evil is not communicable by ordinary means, yet is it readily
excited by inoculation, or the application of putrid matter to a broken
surface. If the odour from the affected parts is any way offensive,
wash them with, and sprinkle round the fold, either a weak solution of
_chloride of lime_, or the disinfecting liquid of Labarraque, articles
which may now be procured from every provincial apothecary. Finally,
let the shepherd _wash his hands carefully_ before going from diseased
to healthy sheep, using, if need be, a little of either of these
solutions; and let him look well to any injuries which his charges may
receive in July, August, and September, for these are the months most
favourable to the occurrence of leg evil.
(147). _Inflammation caused by Maggots._ The insects passing under the
name of "Fly," though most troublesome in August, attack the sheep from
the month of May to September, inclusive, depositing their eggs among
the wool, in general about the tail, the roots of the horns, or any
part which affords, from its filthy appearance, a prospect of suitable
provision for the maggot. When these eggs are hatched, a process which
is, in sultry weather, almost instantaneous, the maggot erodes the
skin, and speedily brings the adjacent parts into a fit condition for
the reception of succeeding numbers of its species.
The backs of long-woolled sheep are, from their exposure, more liable
to be selected by the flies, as a receptacle for their eggs, than the
corresponding parts in such as are covered by a short thick fleece.
No sooner has the maggot begun its operations, than the sheep becomes
uneasy and restless, rubbing itself on stones and trees, and
endeavouring, by every means in its power to free itself from the
annoyance. Teazed by the constant irritation, fever soon sets in, and,
if the sheep be unrelieved by the shepherd's aid, death ensues in
four-and-twenty hours.
It is only lately that attention has been paid to the history of the
insect pests which originate the mischief, so little damage do they
appear to have occasioned in former periods. In a valuable paper,
containing the result of observations made on this subject in the
Highlands, and published in the second number of the _Quarterly Journal
of Agriculture_, they are thus described:--
"The fly which is the immediate cause of this disease, seems, as far as
my observations could extend, to consist of four species, viz.--the
_Musca Ceasar_, _Cadaverina_, _Vomitoria_, and _Carnaria_, of Linnaeus.
* * *
"_M. Ceasar_ is of a shining green colour.
"_M. Cadaverina_, the thorax shining bluish, the abdomen green, like
the _Ceasar_.
"_M. Vomitoria_, thorax black, or dark-blue grey, abdomen dark glossy
blue. This is the common _Blue-Bottle_ or _Flesh-fly_.
"_M. Carnaria_, grey; the thorax has three black longitudinal markings
on the upper surface; the abdomen is checquered, in some positions
shining whitish.
"In all those instances in which I observed them, the green flies were
the first to attack, and this is the common opinion among the
shepherds. After a time, when the larvae (maggots) commenced gnawing the
flesh, the putrid stench, which was thereby occasioned, attracted
numerous other species. The _Vomitoria_ (_blue-bottle_) was very
common, more numerous than both the former species, and perhaps
contributed most to accelerate the death of the animal, after the
others had commenced. The _Carnaria_ was rare. I observed but few of
them, and these seemed not concerned; which is the more remarkable, as
in the fenny counties of England it is said to be most troublesome. All
the species of this genus resemble one another closely, both in
appearance and mode of life. They are exceedingly voracious, feeding
upon carcasses and filth of every description. In five days after being
hatched they arrive at full growth, provided they have plenty of food;
they then cease to eat, and seek to assume the pupa state, crawling
under ground two or three inches. Here they remain about fourteen days,
when the shell cracks, and the imago, or fly, appears. In this last
state, they feed also on putrid juices, sucking them through their
probosces."
The correctness of this description of their transformations I can
attest, from having watched their habits during my anatomical pursuits
in the summer months.
(148.) _Treatment of Fly-blown Sheep._ When the sheep is fly-blown,
dislodge the maggots with a knife, and shake a little powdered white
lead into the wound. Do not apply tar to the abraded surface, as, from
its cauterizing effects, the wound will be enlarged, and a repetition
of the visit speedily ensured. To ward off the onset of the flies,
various substances noxious to them are rubbed or poured upon the wool.
Tar, in small quantities, and of pungent quality, is by some daubed
upon the ears, horns, and tail. Others prefer rubbing a little melted
butter, thickened by flour of sulphur, along the sheep's back: this is
an effectual preventive. Some, again, prefer dressing the sheep, when
in low situations, with the following recipe, which I take the liberty
of copying from Mr Mather's paper on the fly, in the _Quarterly Journal
of Agriculture_, No. XXIV.
"Take of Arsenic, finely pounded, one pound
Potash twelve ounces,
Common yellow soap six ounces,
Rain or river water thirty gallons.
"Boil the ingredients together for fifteen minutes. * * * * The liquid
is in no degree injurious to wool. It cleans and dries the offensive
perspiration of the sheep, and destroys the smell caused by the dew in
the mornings, or by damp hot weather. In most situations, one dressing
in July and another in August will suffice; but as the expense is
trifling, and the process simple, it may be better to apply it more
frequently, especially in low and damp situations." The liquid is
applied only in dry weather. A teapot, or any vessel of a similar form,
is filled with it, and one person pours it on the wool, while another
rubs the fleece to facilitate the passage of the fluid. At the times of
using the solution, all superfluous wool ought to be shorn from the
buttocks, but not too closely.
When the insects are very troublesome, drive the sheep if possible to
higher ground. Examine carefully all wounds and ulcers, however
trifling, and dress them with any simple ointment containing a small
proportion of sulphur, mercury, or white-lead. Lastly, bury all useless
carcasses as speedily as possible, by which means you will keep down
the number of the flies.
(149.) _The Sheep-Fag or Ked_ (_Hippobosca ovina_) and _The Tick_
(_Acarus reduvius_), are destroyed or stopped in their attacks by the
same remedies and preventives detailed in the preceding paragraphs on
the fly.
(150.) _Inflammation produced by the OEstrus bovis._ This insect
infests not only cattle but also sheep and goats, depositing its eggs
on the back of the animal, where it forms a small tumour, in which the
larvae remain from autumn till the commencement of the ensuing summer.
Only the fattest and most vigorous animals are attacked, and the larvae
are very difficult to destroy. Fischer found, from numerous
experiments, that even spirits, and a strong solution of salt, could
not affect them. The fumes of burning sulphur alone seemed to annoy
them, and to it they speedily fell victims. This, however, is a remedy
which cannot be applied to the skin of the sheep, so that our only
resource is the repeated application of turpentine to the tumours on
the back, taking care to slit them up so as to facilitate its action.
(151.) _Sore Teats._ When a ewe is observed to hinder the lamb from
sucking, its teats should be examined. If much inflamed, a poultice
should be applied, and the lamb placed under the charge of another
nurse. Suppuration will thus be promoted, and the matter may be allowed
to escape by making an opening for it at the place it points. If there
is only a little tenderness of the skin, all that is required is the
washing it with a solution either of sugar of lead or sulphate of zinc,
eight grains to the ounce of water.
(152.) _Foot-rot._ No disease occasions more acute suffering to the
sheep, and annoyance to the farmer, than foot-rot, and no disease has
led to longer arguments as to its contagious or non-contagious nature.
Thanks, however, to Mr Dick of Edinburgh, these disputes are closed for
ever, as any one may be convinced, by perusing his clever and sarcastic
paper at page 852, Vol. ii. of the _Quarterly Journal of Agriculture_.
His excellent remarks on the popular ideas of the infectious nature of
foot-rot, I have not space to quote, but shall lay before the reader
his views as to the situations and circumstances which give origin to
the disease.[29]
[29] To enable the reader more easily to understand Mr Dick's
views of this disease, I have added a drawing of the foot of
the sheep, which it may be well to consult before entering on
the subject.
_Fig. 4. Plate._ I. Section of a toe:--_c.c._ Crust of the
hoof; _s._ Sole; _g.g._ Gland which secretes the hoof.
(153.) _Causes of Foot-rot._ "What do we gain," says Mr Dick, "by
enticing the sheep from his native and natural haunts to the richer
pasturage of our meadows or lawns? There the animal enjoys a more
luxuriant repast; it fattens to a larger size, and will, in this
respect, repay the increased allowance which has been made to it. But
instead of moving about in small troops, with the alacrity of the wild
kinds, the sheep are seen in flocks of thousands, moving slowly over
their pastures, and gorging themselves to an extent which cuts short
the thread of life, by the advancement of various diseases. Instead of
wandering from the summit of one peak to another, in quest of a scanty
subsistence, or instead of being compelled to descend from the summits
of the mountain in the morning, and ascend again in the evening, they
are compelled, in many cases, to remain within a few yards of a
particular spot for weeks together, and there engorge themselves to
satiety.
"But what, it may be asked, has this to do with the foot-rot? More, I
am inclined to think, than is generally imagined. The hoofs of the
sheep being intended to receive a degree of friction from hard
surfaces, are not acted upon when the animal is placed under such
circumstances; and the necessary consequence is an overgrowth of the
hoof. The crust,--the part naturally intended to support the weight of
the animal, and to endure the greatest share of fatigue,--is here
allowed to grow out of all due bounds, because the softness of the
pasturages, upon which it now moves, presents little, if any, of that
rough friction to which the feet of the animal is naturally intended to
be exposed. The crust, therefore, grows unrestrained, until it either
laps over the sole, like the loose sole of an old shoe, and serves to
retain and accumulate earth and filth, or is broken off in detached
parts, in some cases exposing the quick, or opening new pores, into
which the particles of earth or sand force their way, until reaching
the quick, an inflammation is set up, which, in its progress, alters or
destroys the whole foot."
* * * * *
"The finest and richest old pastures and lawns are particularly liable
to this disease; soft, marshy, and luxuriant meadows are equally so;
and it is also found in light, soft or sandy districts. In the first of
these it is perhaps most prevalent in a moist season, and in the latter
in a dry one; in short, it exists to a greater or less extent in every
situation which has a tendency to increase the growth of the hoofs
without wearing them away, and more especially where they are kept soft
by moisture. It is so prevalent in fine lawns and pleasure grounds,
that they are, in many instances, reduced in value to a mere trifle as
a pasture for sheep; they are said to be _infected_ with this disease,
and having once become so, the vicissitudes of _seven_ seasons are
scarcely sufficient to destroy the contagion! A luxuriant herbage, on
soft pastures, is equally subject to it; and, in both cases, the
disease is increased in a wet season.
"The reason why, in these situations, sheep are so liable to the
disease, is quite obvious. They are generally brought from lands where
their range of pasturage was greater than in these situations. In their
former state, from the exercise which the animal took, and the nature
of the grounds on which it pastured, the hoof was worn down as it grew;
but, under the state in question, the hoofs not only continue to grow,
but, where the land is moist, that growth is greatly increased; and the
animal does not tread upon hard ground, nor has it exercise to wear
them down. Now, in the case of man himself, when the nails of his
fingers or toes exceed the proper length, they break, or give him such
uneasiness as to induce him to pare them. And the same takes place with
the hoof of sheep. But there is this difference in the case of the
latter, that when their hoof once breaks, as the animal has not the
power of paring it, the part thus broken must continue a wound. Some
parts grow out of their natural and proper proportions; the crust of
the hoof (_c.c._) grows too long; and the overgrown parts either break
off in irregular rents and unnatural forms, or, by over-shooting the
sole (_s._), allow small particles of sand or earth to enter into the
pores of the hoof. These particles reach the quick, and set up an
inflammation, which is followed by the destructive effects which are
too well known to require description.
"Similar effects are produced on soft, wet grounds. The feet, in such a
situation, are not only not subject to a proper degree of friction to
wear down the hoofs, but the growth of the hoofs is materially
increased by the soft and moist state in which they are kept. And this
state renders the feet the more liable to the disease, as it opens up
the pores of the horn, and allows the earth or sand to penetrate, and
wound the quick, in the manner I have already stated. On soft sandy
ground, of a dry nature, the same circumstances may occur. The soft
sand gives way by the weight of the animal, and the crust of the hoof
is not worn down. The sand penetrates between the sole and the crust,
as has been already explained, and produces inflammation. The disease,
however, is not so common on sand as in the other situations to which I
have alluded, the sand seldom being found in such a loose state."
Another variety of foot-rot is produced by the friction of long grass
between the hoofs, but is mostly confined to hill sheep, when first
pastured on lowland districts. These animals, from having been
accustomed to collect their food on extensive ranges of bare pasture,
are more exposed than heavy breeds to this frequent exciting cause of
the complaint. The rubbing of the grass frets the skin in the cleft of
the hoof, the gland in that situation swells, becomes enlarged, and
suppurates, and in no long time the animal is compelled to rest upon
its knees.[30] This complaint is, however, more readily remedied than
the former, and does not cause nearly so much suffering to the sheep.
[30] _Fig. 5. Plate._ I. Gives a view of the inner surface of
the toe of a sheep, with the interdigital gland laid open.
_g._ The gland.
_d._ The duct of the gland, opening upon the anterior surface
of the leg.
When the interdigital gland is much enlarged, it becomes
necessary to cut it out. This ought to be a last resource, as
the part appears to be of too much importance to be easily
dispensed with.
(154.) _Treatment and Prevention of Foot-rot._ As foot-rot, in nine
cases out of ten, is an attempt on the part of nature to get rid of a
portion of the hoof, which ought, in the proper course of things, to
have been worn away as fast as it appeared, the prevention and
treatment of the first stage of the complaint will naturally suggest
themselves. "As this disease," says Mr Dick, at the conclusion of the
aforementioned paper, "arises in consequence of the hoofs not being
exposed to sufficient friction to wear them down, or keep them in their
proper state, or where their natural growth is increased by the nature
and moisture of the ground, the hoofs of all the flock should be
regularly rasped or pared at short intervals, say from eight days to a
fortnight, according to the rapidity with which a particular pasture
produces the disease. In certain situations, they might be made to
travel upon a hard surface, similar to natural sheep tracts, or be
folded in a place purposely prepared, upon which they could move about
and wear their hoofs. For that purpose, they should be placed in it
every day."
When foot-rot has fairly commenced, pare the hoof from the affected
part, and trim away any ragged portions, wash the foot with soap and
water, and place the animal in a situation where as few irritating
things as possible will be in the way of the tender surface, and give a
purgative. If not properly attended to, the suppuration soon terminates
in mortification. Cleanliness in every stage and variety of foot-rot,
is of the first importance. Many corrosive preparations are recommended
for the cure of this disease, but I have decided objections to one and
all of them. When the foot is clean, endeavour, by frequent
applications of soap and water, to keep and treat the ulcers as
directed in paragraph 110.
(155.) _Inflammation produced by Insects in the Air Passages._ Much
annoyance is caused to the sheep by the presence of animals in the air
passages. The _OEstrus ovis_ deposits its eggs on the margin of the
nostril in autumn; these are soon hatched, and the larvae immediately
find their way up the interior of the nose, till they arrive at the
frontal sinus, a cavity situated between the layers of the frontal
bone, and of considerable size in the sheep. Here they remain till the
following spring, when they quit their hold, become winged insects, and
enter upon the career of torment so ably gone through by their
predecessors.
The _Pentastoma_, an animal supposed at one time only to exist in the
frontal sinus and lungs, and on the surface of the liver, of the dog,
wolf, and horse, as well as in some reptiles, has been discovered by an
able naturalist, my friend Mr Rhind of Edinburgh, in the frontal sinus
of the sheep. It spends its whole existence there, and is distinguished
from other entozoa by having the mouth between two pores on each side,
through which a spicular process comes out. Figure 3, Plate VII. is
taken from a drawing kindly furnished by Mr Rhind.
(156.) _Removal of Insects from the Nostril._ The _OEstrus ovis_
occasions much distress to the sheep at the moment of depositing its
eggs within the nostril. The animal on feeling the movements of the
fly, rubs its nose against the ground, or, carrying it low, darts off
at a rapid pace, vainly endeavouring to escape from its tormentor.
During this period, a thin limpid fluid distils from the nostrils,
leading a careless observer to confound the symptoms with those which
accompany Coryza. In general the irritation is now terminated, as,
while in the larvae state, the insects are incapable of offensive
measures. If they are clustered in considerable numbers in the frontal
sinuses, they will doubtless lead to great suffering, parallel to what
is recorded to have followed the nestling of insects in the same
situation in the human being; and it is, therefore, advisable, when the
cause of sturdy (paragraph 169) is in any way doubtful, first to apply
those substances to the nostril, which are calculated to destroy both
these larvae and the _pentastoma_, should they happen to be there.
Tobacco smoke is the only available remedy, and a very good one,
being easily brought in contact with the worms, and, when properly
administered, certain in its effects. One person secures the sheep
holding the head in a convenient position, while another, having half
filled a pipe with tobacco, and kindled it in the usual manner, places
one or two folds of a handkerchief over the opening of the bowl, then
passes the tube a good way up the nostril, applies his mouth to the
covered bowl, and blows vigorously through the napkin. When this has
continued for a few seconds, the pipe is withdrawn, and the operation
repeated on the other nostril.
The round hair-worm (_strongylus filaria_) has been found in great
numbers in the trachea and bronchii of calves by Camper, and of the
sheep by Daubeuton. It has also been found in the reed and duodenum of
the latter animal by Rudolphi. Two other species of the genus
_Strongle_, the _S. contortus_ and _S. filicollis_, have been detected
in the sheep, the former in the belly, the latter in the small
intestines. They all appear to originate only in such sheep as are
exposed to the sapping influence of low damp situations, combined with
stinted diet. Those occuring in the air tubes give rise to irritation,
and a consequent harassing cough, which is only to be arrested by
removing the sheep to a dry airy locality, and a nutritious pasture.
Unless portions of the worms are thrown up during coughing, they cannot
be pronounced with confidence to exist, as the symptoms which they
produce are very similar to those which accompany the two following
diseases.