SHEEP – MANAGEMENT.

New Zealand Journal of Agriculture, Volume VI, Issue 6, 16 June 1913, Page 575

SHEEP - MANAGEMENT.

VIEWED FROM THE HEALTH STANDPOINT;

C. J. Reakes, D.V.Sc., M.R.C.V.S.

; Continued from April issue. ' ■ ; Parasitic Diseases. INTERNAL parasites still cause' considerable loss to sheepowners, though far less than was the case some fifteen years , ago, when heavy mortality occurred every , year, among hoggets especially,-throughout the west coast 1 of the North Island, principally as a , result of the attacks of lung and stomach parasites. At that time, and to some extent since, socalled lung-worm was looked .upon as being the ’ more ■ serious affection, but the probability ’is that then, as now, the presence of small hairlike worms in the fourth stomach was really responsible for the greatest proportion of deaths, lung-worms being present in the animals at the same time.. It must not be assumed that I suggest that these lungparasites are not seriously dangerous, for they are, and many young

sheep' have died from the effects of their presence. But the stomachworms are the worst pest, and it is necessary, in districts where the conditions ’ of soil 'and ’ climate are favourable to their dissemination, to take practical precautions to guard against their attacks. These precautions are summarized in the following extract from the Bulletin on the subject, No. 3 (new series):— • ; ?; “ To realize fully the value of preventive measures, the life-history of the parasites, so far as known at the present time, must be understood. Each animal suffering from the disease daily passes innumerable ova (eggs), and, possibly, also newly hatched worms, or mature female worms, loaded with eggs, who, - having fulfilled their function, die, leaving the eggs virile (a single female may produce thousands). The eggs deposited on the pasture are ready to be taken up by sheep feeding upon it, who thus continually renew their trouble. In lowlying, wet pastures these worm- 4 eggs ’ and, possibly, also immature worms developed from them after deposition upon the ground-surface, or voided by the infected animals, are able to retain their animal vitality outside the animal body for a much, longer period than on dry and sunny land. Therefore, removal from contaminated land to dry, well-drained, not-heavily-grassed paddocks is not only essential as a matter of treatment, but the depasturing of young sheep upon such Paddocks is one of the best preventive measures. It is a notable fact that a few parasites may be found in the fourth stomach of a very great proportion of healthy and vigorous young sheep it is only when present in large number that they do noticeable harm—seeing that they do not multiply within the body, it is obvious that suitable outside conditions are necessary to enable them to infest sheep badly. These conditions, as already stated, are to be found in lowlying, wet, badly drained pastures, in heavily grassed land where surface water does not get away freely, and also, during wet seasons, on good, . well-grassed, otherwise sound paddocks. Whenever such conditions, favourable to the propagation of the parasite, exist, a close watch should be kept, and at the first clear indication of parasitic gastritis the flock should be transferred to another paddock -the bestdrained and driest available.”

As regards lung-worm,' the same preventive measures apply, the conditions of soil, pasture, &c., which are favourable to the spread of the stomach-worms, being equally favourable to the worms infesting the lungs.

- The sheep-maggot fly has been known to be present in the Dominion for some years past, and at times causes trouble. - Though we cannot hope to . rid the country of this insect, yet by careful shepherding , and /precautionary measures it can be prevented from doing any serious harm ■to our flocks. It deposits its eggs on dirty wool, and the filthier this is the better it seems to suit the fly. The maggots hatched out from the eggs afterwards burrow into the skin, or,, if a slight wound be present, it affords them a still easier means of gaining entrance. The obvious precautionary measures are to maintain the sheep in as cleanly a condition in regard to their wool as possible. Proper dipping, crutching, dagging, &c., are necessary; and if scouring be present care should especially be taken to keep the posterior parts clear of dung-clogged wool, and, further, measures should be taken, by change of feed, &c., to stop the scouring if possible. If a wound is sustained it should be promptly dressed with tar. In the case of a sheep being “ struck,” the wool at the part should be closely clipped off and strong antiseptic dressings applied .to the part, all maggots found being carefully removed and destroyed. .. . Dietetic Disorders. ■ . • In order to maintain sheep in good health and condition care is necessary in the matter of the class of pasture on which they are placed. - Rough, rank grass, especially of autumn growth, is not a suitable food for sheep, and at times considerable loss occurs through sheep being, grazed on feed of this kind. A form of chronic indigestion is set up, resulting in a certain amount of fermentation occurring in the food in the stomachs or the bowels, which is apt to cause trouble in some form or. other. ■ln some cases the sheep simply die, in others they do badly, having fits of scouring alternated by constipation. Another condition resulting from this improper , feeding is the development of an inflamed condition of the skin of the face and ears, causing such severe irritation that the affected animals, in their endeavours to obtain relief, rub their heads against fence-posts, logs, or on the groundsurface, often causing abrasions of the skin when doing so. This breaking of the skin enables outside germs to gain entrance and set.up. a condition of dry gangrene, the animals then presenting a most unsightly appearance. The whole of the skin of the head is converted . into a sort of dry scab, with, matter beneath, the eyes are inflamed and often sightless, and unless proper treatment be applied in time death frequently

occurs. It has been noted that when a large proportion of deaths do occur in an'' affected flock' the liver has been found in a state of fatty infiltration, and the fatty condition of this important organ has naturally been a factor in" the - digestive derangement which has preceded’ "the skin trouble. This affords another illustration of. the necessity of so managing a flock, of breeding-ewes especially, that the animals do not become unduly fat at any time. Breeding-ewes have been at times heavy sufferers from facial eczema (or facial dermatitis), as this trouble of the skin of the head is termed. Unless in seasons when a heavy growth of rank autumn feed occurs, when it is difficult, and at times impossible, for owners to avoid depasturing their sheep upon it, there should be no reason for the sheep being ‘ exposed to the unfavourable feed-conditions liable to set up this affection, and careful management in this direction will prevent its occurrence. If it does occur, the prompt application of proper treatment will check it and prevent any severe loss. Change to short sweet pasture is the first measure to be adopted, and at the same time a strong solution (5 per cent.) of Lysol, Izal, or Jeyes fluid should be applied to the skin of the face and ears once daily for three or four days, care being taken to prevent it getting into the eyes or on the inside of the lips. This quickly allays the irritation present in the skin during the earlier stages of the trouble. . In those cases where facial trouble does not appear, but the sheep are simply sick, or are dying from the severe digestive disturbance set up by the rank, rough feed, the necessity, for a change to a better paddock is obvious ; and where the animals are considered of sufficient value to be worth the expenditure of the time and labour necessitated by the administration of medicine, one or two 3 oz- or 4 oz. doses (according to age) of Epsom salts dissolved in thin gruel are of great value. Great care must be exercised in drenching the sheep or they will be subjected to the risk of being promptly killed by the liquid finding its way into the windpipe and the lungs instead of into the stomach. Lambs when on rape are liable to develop a skin affection, the skin of the ears especially ' becoming swollen and inflamed, general constitutional symptoms, which may result in death following unless the animals are promptly removed "and given a change of diet in a grass paddock, when they soon recover. \ Another form of skin trouble . arising from the same cause is that, known as “ rape-scald,” the skin along the back being usually affected

in this case. This has the additional disadvantage of impairing the value of the pelt. Here, again, a change to less-stimulating feed is required.

. , Some years, since a considerable mortality occurred, every year in the South Island among sheep, usually hoggets, when . feeding on turnips. It was due to a -disease closely resembling braxy. The cause lay in a germ present in the soil, which gained entrance into the systems of the animals.: There is every reason to believe that one important feature in the prevalence of the trouble at that time lay in the dissemination of infection from the carcases of dead sheep left to rot on the ground-surface. At the same time, apart from this, there can be no doubt that the provision of a run off from the turnips on to a good grass paddock, by providing a variety of diet and a better camping-ground, is an important factor in avoiding loss from this disease. An additional advantage is that the animals do better with a mixture of other food with the turnips, the admixture of grass food aiding the digestion of the whole, and enabling them to obtain the greatest benefit from the turnips eaten. Dry feed, as oaten chaff, hay, &c., would answer the same purpose, but it means expense, and the animals do not always take readily to it. . Southern farmers have largely availed themselves of the knowledge gained regarding this disease, and the losses from it are now very small compared with those of some years ago. Conclusion. In concluding' this paper T would once more impress upon sheepowners the fact that good management is essential to successful sheepfarming, and that by the exercise of care and forethought much loss from disease in its various forms can be avoided. Much of the information given is based on the observations made by Dr. Gilruth, who, during his tenure of office in New Zealand, did an immense amount of good work in connection with sheep-management and' sheep-diseases.