BLOOD-POISONING IN SHEEP.

Sun (Christchurch), Volume III, Issue 857, 8 November 1916, Page 2

BLOOD-POISONING IN SHEEP.

PRECAUTIONARY MEASURES AFTER SHEARING OR DOCKING. Blood-poisoning in sheep and lambs now causes a mortality very small in comparison with that of a few years ago, when the annual death rate caused by it was far too heavy. The "Journal of Agriculture" deals with the subject in the latest edition. The condition of blood-poisoning is set up through a particular micro organism (the bacillus of 'malignant oedema) gaining entrance ! into the system of the sheep or the i lamb through wounds or abrasions accidentally occurring during shearing, or through the wounds made in the operations of cutting and tailing. In nearly I every case investigated, it has been shown that the animals became infected through dust or dirt from eonI taminatcd sheep yards or their immediate surroundings coming in contact with the freshly inflicted wounds. Lambs arc now usually cut and tailed in temporary yards formed by hurdles in paddocks, and this practice has given successful results from the point of view of prevention. But it alone is not always sufficient. In one instance which came under notice there was no reason to believe that the yards used were infected, but the human element failed badly. The instrument used was a knife which the operator (whose ideas of cleanliness were far from being up to date) was in the habit of making use of for all sorts of purposes, including the skinning of dead sheep, and it was evident that he took no pains to keep it properly clean. A number of lambs died of blood-poisoning within 48 hours, and a very careful and thorough investigation made on the spot failed to show any other source of infection than the dirty knife.

It must be remembered that the particular micro-organism which causes this form of blood-poisoning is one that reproduces itself by spores (which may be likened to seeds), and that these spores can retain Iheir vitality outside the animal body, especially in the soil, or in the dirt which accumulates in the handle socket of a dirty knife, for a long period. A ground surface badly fouled by dung, or a knife fouled by use on dead sheep and not properly cleansed afterwards, is always dangerous from the point of view of blood-poisoning. The majority of sheep yards are evidenty not contaminated by malignant (edema, since no trouble caused by thte disease occurs at. shearing time among sheep held in them: but whenever sheep die of blood-poisoning after shearing radical steps should be taken to prevent future trouble. One or two things must be done:—

(1) The provision of new yards on clean ground. As this necessitates also the erection of a shearing shed, it means the incurring of considerable expense. At the same time there are some shearing sheds in the Dominion which could

with advantage bo abolished and re-, placed by better and more up-to-date buildings. (2) The removal of the whole of the surface soil of the yards to a depth of at least 6in., and preferably Ift. Saturating the newly exposed surface with a solution of non-poisonous dip of a strength not less than 5 per cent., and after this has dried giving a heavy . coating of lime. After applying the! lime, the replacing of the removed soil. by tdean earth taken, in flat country, from well below the surface (but never from land inclined to be swampy), or from a cut into a hillside whenever possible. Lambs should never be eut and tailed in sheep-yards, as, even if the organism of malignant oedema be absent, they are more susceptible to the effects of the contamination of newly inflicted wounds by dirt than are older sheep. "Where outbreaks of this disease have occurred at shearing time it has been at times noted that contamination of the shearing shed itself has been sus- '■ pected by the owners as being responBible. Our usual experience, however, is ' that the source of the trouble lies in the yards; though some of the sheds, to- ( gether with the ground surface below their gratings, have certainly been in a I \cry dirty condition—one which, on ! general principles of reasonable sanitation, should not exist. The symptoms of blood poisoning are

very pronounced, and are not likely to jbe mistaken for anything else. They I usually appear within from 24 to 48 hours after shearing or docking and tailing. The most characteristic feature, ;is a well-marked swelling, wjiich quickly becomes dark coloured—in fart, almost black —and gangrenous. In the earlier stages the animal moves stiffly [when forced to movement, gradually bei comes more and more dull and listless, ,is off feed, and is obviously in a very I bad way. Marked lameness is noted :in the early stages, when infection gains entrance through wounds in the ■ leg after shearing. In gTown sheep, re- : covery sometimes takes place, especially if the point of infection is situated on the lower portion of the leg. Whatever molality occurs is all over within four or live days at the outside in the case of sheep, and usuaV" within two ' days with lambs. Attempts at curative treatment are of practically no value. Prevention, which can be secured by the possession of the necessary plain knowledge and the putting of it into practice, is the one thing necessary for the avoidance of loss through this particular manifestation of blood poisoning.