Chapter VII: Diseases of Sheep (3)

This excessive accumulation of fluid within the brain leads, as might be expected, to the dilatation of the skull, and to the absorption of its walls, when the bones, young though the animal be when affected with sturdy, can no longer be made to yield. For this reason the skull, towards the termination of the disease, generally becomes thin and soft in front of the root of the horn, and in this way offers a spot which, from its being easily pierced, is frequently made the seat of surgical operations. Other parts of the skull also undergo considerable thinning, more so indeed than in front of the horn. The attention of the farmer has hardly, if ever, been called to this fact, though I believe that, for one instance in which perforation occurs in the frontal bone, it will be noticed a score of times on the sides of the head. In a head with which I was favoured by Mr Grieve, Branxholm braes, each temple, exactly beneath the superior extremity of the upright branch of the lower jaw, displayed a circular opening entirely through the bone, wide enough to permit the passage of an ounce bullet.

Whatever may produce pressure on the brain, the symptoms which indicate it are nearly always the same. The sheep has a dull, stupid look, turns very often round and round, and will, when water is in its way, stand staring at it till at last, giddy and confused, it plumps fairly in. If, when the symptoms are very unpromising, convulsive movements should occur, they may be taken as a favourable sign, as they indicate a diminution of the pressure on the brain. A minute description of the morbid appearances in hydrocephalus could serve no good purpose, I therefore pass on to the prevention of sturdy.

(170.) _Treatment and Prevention of Sturdy._ The variety caused by hydatids can only be prevented by the use of dry, well grown, wholesome food. Dr Jenner found that he could cause hydatids to form in rabbits at will, by feeding them on green succulent provision; and it is well known that this form of sturdy prevails among sheep chiefly in marshy places, as the fens of Lincolnshire.

Water in the head is generally induced, as first pointed out by the Ettrick Shepherd, in the _Farmer's Magazine_ for 1812, by the back of the animal being chilled, as is evident from the following facts:--

"1. It is always most general after a windy and sleety winter.

"2. It is always most destructive on farms that are ill-sheltered,
and on which the sheep are most exposed to those blasts and
showers.

"3. It preys only on sheep rising their first year, the wool of
which separates above, leaving the back quite exposed to the wet
and cold.

"4. If a piece of cloth or hide is sewed to the wool, so as to
cover the back, such a sheep will not be affected with the
disease."

Bratting is therefore the best preventive, and it is as cheap as it is effectual. One pair of old blankets, worth only some four or five shillings, will furnish coverings for forty hogs, and if laid carefully aside in spring, they will continue serviceable for two or three years. An operation can avail nothing--slaughtering the sheep is therefore the only expedient.

When the existence of a hydatid near the surface of the brain is denoted by the skull yielding, at some particular spot, to the firm pressure of the thumb, its extraction must be set about in the manner described in paragraph (118), where I have also given my objections to the common modes of operating.

(171.) _Trembling._ Several affections are included under the name of _trembling_ or _leaping-ill_, all having, in common, more or less of the symptoms which these names denote. They may be considered as arising from exposure to cold and damp, especially on long fatiguing journies, as in bringing sheep from the Highlands to the south of Scotland, when it frequently prevails to so great an extent, on reaching the low country, as to oblige the shepherd to leave eight or ten behind him at every stage. Injuries of the loins, either inflicted by themselves in jumping and running, or by others from rough usage in the fold, are common causes of the disease; but in this variety the hind quarters only are powerless. Another species is owing to oppression of the brain from congestion, in this way resembling incipient sturdy, and occurring only in very fat sheep.

(172.) _Treatment of Trembling._ The first variety is best met by rest, shelter, and a supply of nutritious food; but as the animal is incapable, in many cases, of collecting it, the shepherd must lift it from one rich part of the field to another, so soon as it has cleared away the grass within its reach. In the second kind, as caused by accident, the sheep must be slaughtered, as, should a cure be attempted, the treatment will be too tedious and complicated to succeed in ordinary hands. Copious blood-letting, and doses of Epsom salts, will be found of most advantage in the third species; but if the sheep can be disposed of so much the better, as this kind of _trembling_ is almost certain, unless combated by energetic depletion, to end in sturdy.

(173.) _Wood Evil_ is nothing more than a cramp of the hind legs, owing to water dripping upon them from trees after a shower of rain, and is best treated by enveloping them in flannel, wrung out of hot water; but if the sheep is at the time very chill, gentle friction must first be used, else dangerous consequences will ensue. Rubbing with warm turpentine has been recommended, and is apparently worthy of a trial.

(174.) _Inflamed Eyes._ The pollen of flowers getting into the eyes while feeding, is a common cause of this annoyance, which need not be described, as, from being visible, it is known to all. Examine the eyes, and remove any irritating body. Then, if the disease be of recent date, bleed the animal largely from the jugular vein, and give it several doses of Epsom, or Glauber's salt. After the inflammation is subdued, or should it be in the suppurating stage when first noticed, hold the lids asunder, and drop upon the eye, three or four times a day, a solution of white vitriol, five grains to the ounce of water. Where this cannot be had, pure _cold_ water dashed against the eyes and head several times a day will serve as a substitute.

Though sheep are not so much incommoded by blindness as other animals, from the instinctive care usually taken of the sufferer by the rest of the flock, still such a mishap should always be prevented by energetic treatment at the commencement of the symptoms.

(175.) _Soft Cancer of the Eye_, or, as it is also called by medical men, _Fungus Hematodes_, is of very rare occurrence among sheep, and indeed would not have deserved a notice here, were it not that, from being a malignant disease, it might be looked upon as quite incurable. I can only describe it as a soft, spongy tumour, rising from the bottom of the eye, involving all the textures of that organ, so as to render them scarcely recognizable, and bleeding on the slightest touch. It is readily removed by passing a stout thread through the front of the eye with a needle, so as to afford the operator a hold by which to pull it outwards with the left hand, while, with the right, he cuts round it with a narrow-bladed knife. The operation is attended only with slight pain, but must not be considered the sole curative means; the sheep must have, at the same time, a frequent change of pasture, to prevent a recurrence of the tumour.

There is a very large tumour of this description at present in the museum of Guy's Hospital, taken from a sheep which recovered perfectly.