Sheep Farmers! Guard Against Sleepy Sickness of Ewes

New Zealand Journal of Agriculture, Volume 61, Issue 1, 15 July 1940, Page 5

Sheep Farmers! Guard Against Sleepy Sickness of Ewes

In a jew weeks time lambing will begin in certain parts of New Zealand, and the sheep farmer must guard against antepartum paralysis of ewes, or “sleepy sickness,” as it is sometimes called. This trouble can cause substantial losses in certain years, and the elimination of losses is one of the simplest ways of increasing production— matter of national as well as individual' importance at the present time.

By

A. D. M. G. LAING.

Veterinarian, Hastings.

r T"’WIN lamb disease is another name TWIN lamb disease is another name for this trouble, as ewes suffering from it are found to have been carrying twin lambs in the very great majority of cases. The first signs of this disease are noticed from -ten to 20 days before the ewe is due to lamb. The animal is dull, off her feed, and tends to keep apart from the rest of the flock.

The earliest noticeable sign is frequently a loss of control over the limbs, manifested by tripping up or crossing the forelegs when driven. Later, she will stand stupidly and be moved only with difficulty. The eyes appear glazed and. sightless. The affected animals may also stagger and/or walk in circles. As she gets worse, the ewe gets “down to it,” collapsing after walking a few paces if raised to her feet. She may live for several days in this condition, death occurring in a few days after the first signs were noticed.

Results of Post-mortem

If a ewe which has died of this disease is opened up after death she is nearly . always found to be carrying twin lambs. The general condition of the body and organs- is good, with the noticeable exception of the liver, which is quite abnormal, being enlarged, pale yellow, greasy ,to the touch, and very easily broken. There is not, in fact, any healthy liver tissue left. Some of the internal body . fat may have a patchy, parboiled appearance. '

Treatment and, more important still, prevention of any given disease must be based on a proper understanding of what causes that disease.. In the ewe

the cause is nutritional in the case of ante-partum • paralysis or “sleepy sickness.” That is to say, it is associated with a feed shortage or a lowering in the nutritional value of the feed during the latter part of pregnancy. It is desirable, therefore, to give a very

short and necessarily sketchy, description of the extremely complicated process by which the sheep converts pasture into flesh and blood, etc. '

Digestive Balance

A balanced proportion of the three main food factors, proteins, fats, and carbohydrates, is required. These are all broken down by the digestive juices and action of the liver into simple substances, the waste products

being excreted. These’ simple substances are carried by the blood fluid to the muscles, and there combine with oxygen absorbed from the lungs, the resulting heat being the energy by which the body lives. A number of mineralsphosphorus, calcium, iodine, etc. —are also essential to life and to the satisfactory working of the processes outlined above. It must be emphasised that the liver plays a very essential part. When the food intake is in excess of the bodily requirements the surplus is stored as fat. If the daily food is insufficient, then the fat reserves are called into use. The liver is the organ by means of which the body reserves of fat are converted into the simple substances, in which forms alone they can be made use of to support life.

Time Nourishment Is Required

An important fact which must be emphasised is that just as milkingcows require so much feed for the maintenance of their bodily requirements and so much more for milk

production, in precisely the same way the in-lamb ewe requires so much feed to keep herself and so much more to develop the one, two, or three lambs she is carrying. The important point, however, is that these lambs do not require nourishment in an evenly-increasing ratio throughout the period of pregnancy. In the case of the ewe, in fact, it may be stated that during the last five weeks before lambing she is called upon to supply half the total growth requirements of the lamb or lambs she is carrying. In other words, if she is carrying twin lambs during that last five weeks the ewe must evolve from her own body roughly growth requirements equal to one lamb.

Strain on Liver

It will readily be appreciated, therefore, that when the feed of a pregnant ewe carrying twin lambs falls off in quantity and/or quality during the last month before lambing, when the requirements of the twin lambs she is carrying are so very high, a very heavy strain indeed is put upon that

ewe’s liver in converting her body fat into those simple substances that have been mentioned, in which form alone this fat can be made use of. In the case of ante-partum paralysis, what does happen is that these several factors result in the formation of injurious substances. The presence of these injurious poisonous ■ substances causes the characteristic symptoms of the disease and the gradual breakdown of the whole liver, of which the quite abnormal appearance is so characteristic on post-mortem examination. As the saying goes, “Prevention is better than cure,” and of no condition is that more true than ante-partum paralysis.

T reatment

Before discussing prevention, let us consider treatment. Nothing can be done once the case is far advanced, as the liver has become useless. f In the early stages, however, while there is still a desire for food and the ewe can move about, the administration of up to a Jib of molasses daily is indi-

cated. Glucose is more expensive, but, perhaps, more easily administered, and it can also be given in the form of a 10 per cent, solution by the rectum as an enema, and must then be at blood heat. The object of the administration 'of substances such as glucose, molasses, or sugar is that they help the body against the poisonous substances which have been formed, as already outlined, from excessive use being made of body fat.

As constipation is usually present, loz to 2oz -of Epsom salts, once only, at the start of the treatment are of value. Do not repeat the salts. If the ewe lambs, the symptoms will disappear. It is most essential that the ewe under treatment be given the most nourishing and succulent feed available— barley, young grass, and so on. If these are not available good-quality hay, preferably leguminous, sprinkled with a mixture of one part of molasses to five parts of water, is a fairly good substitute.

Particularly where very early lambing is the practice, accompanied as it occasionally is in certain years by a falling-off in the early spring in the quality and quantity of the pastures, due to climatic conditions, it is advisable that all ewes on such properties should be accumstomed to hay as a reserve feed.

Prevention

In regard to prevention, no deficiency of calcium or any other mineral in the animal body has been diagnosed on this disease. A calcium or .lime deficiency does, however, occur in lambing sickness, but that' is a different disease. It is not confined almost entirely to ewes bearing twins as is ante-partum paralysis. Prevention is on common-sense lines, that is: — ’ (1) The management of the ewe flock should be directed towards a slow rise

in condition from tupping time to, lambing time. If there is likely to be a falling-off in the feed in either quantity or quality it is obvious from what has already been stated that it is much less harmful for it to occur during the first four months than in the last month before lambing. Such a practice will also be beneficial to the ewe’s milk flow. (2) Where paddocks are not topdressed, a lick composed of equal parts of bone-meal or bone-flour and salt should be made available for the ewes. (3) If heavy frosts occur, during the month before lambing is to begin, or if there is any other factor which tends to lessen the quality of the feed, steps should be taken to supplement it in order to prevent that falling-off in nutrition which is the cause of the disease. (4) When cases of ante-partum paralysis have occurred, or where there is reason to suspect that they may occur, where the flock is in high condition daily exercise appears to be of considerable value. During such

movement it is easier to pick out ewes in the very early stage of the disease (that is, loss of control of the limbs as shown by tripping up when driven), and treatment and special feeding when they are picked out then will give good results. A useful plan is to muster the affected flock daily and drive, them slowly for half a mile or so to good pasture and back again after one or two hours. It is, of course, fully appreciated that circumstances on particular properties may make it difficult or impossible to carry out the measures mentioned in their entirety. It is suggested, however, that, should the climatic and pasture conditions which cause the disease occur during the next few weeks, it will be advisable for the sheep owner to carry them out as far as possible. As another proverb goes, “A penny saved is a penny earned,” and a ewe saved, plus twin lambs, is worth a good many pennies.