BUSH SICKNESS,

Dominion, Volume 5, Issue 1527, 24 August 1912, Page 8

BUSH SICKNESS,

PROGRESS OF THE INVESTIGA-' ...;•..:. Tioxs. DEFICIENCY OF AVAILABLE-.IKON. An interesting review of the position iii. regard to : the progress' of tho bush sickness, investigations which, are being OMTiejl out in the Day of Plenty district is given in ; the -/August number of the Journal of tho Department of Agriculture by Jlr. C. J. Koakes, head of tho Live Stock Division of the Department. Mr. Beakes covers tho matter in the following words:—This investigation has., been carried out steadily aud systematically during the year, and a very decided advance haa been made in our knowledge of the condition.., All the evidence gathered points to tho condition being ono of malnutrition'rather than of disease, properly speaking, and I have therefore adopted the term "biish sickness"' in connection with it, instead of "bush, disease" as heretofore.. Mr. B. C. Aston, F.1.C., Agricultural chemist, 'has been closely associated with me throughout, as has also Air. H. A. .lteid, F.E.C.V.S., the latter especially in connection with the pathological side of the work, while Jlr; J. Kerrigan, iM.K.C.V.S., Veterinary Supervisor, who , took up his residence at itotoruii in July Inst, has since ■ supervised the experimental work, giving it close and caretul attention. Considerable assistance was also rendered by Mr. I{. Alexander, Inspector of Stock for the district, whose knowledge, both of the affected country and of the so-called "disease," has proved of great value. I stated in a progress report last year that a series of experiments on tho lines of applying various soil dressings to selected plots had been commenced. 'Some'of these experiments have bee:i concluded, but others, where good results have been obtained, are still in progress. In view of the evident-obscurity, and complexity-of the problem to be solved., it was realised from-.-the beginning that if a successful ultimate result was to be hoped-for the work must be carried out carefully and systematically, even though involving an apparently long period of time. Thus, certain experiments which commenced in January of last year are still in progress (and will in all probability continue for some months to come), the animals concerned in them still, remaining in good health—a most satisfactory state of affairs. Mr. Aston.has carried out.a large mass, of further work-in-the analyses, of soils,, herbage,- water, the urine ( blood, internal 'organs, bones, and other tissues of affected animals, together with comparative analyses of, similar" material from outside districts/- Mr.--Kerrigan,- being on the spot; has. been able to make careful observations, and post-mortem examinations of affected animals; while Mr"; Reid, at the Wallaceviilo Laboratory, has conduced fuTther'.feeding' experiments and pathological .examinations of animal .specimens. -.\ The year's work has resulted in a valuable line for further research having been ppened that a deficiency of available, iron is probably responsible for the trouble—and- though it would be> prema- ' tiire' yeVtb affirm certainty on this point, it .'certainly "looks , most promising. In any case, the field of investigation has. now' been narrowed down considerably, and I. consider.'.the ,outlook 'very hopeful..:. -.-. - The'Soil-Dressing'Experiments. . ; . Those' soil-dressing.; experiments .which have .given good: results uiay.be .summarised *i^follow":—': ■•".' ■:', ''/■ . '; :(a)'. Three',:ypung.'.cattle (steers) brought in"'fronr healthy; country were placed on a ■top-pressed paddock' of 4. acres which had.Tbeeri'fenced off from a large paddock; ■- Outside the 4-acre enclosure, on exactly similar': pasture (but.with.no topdressing);, .and .exactly land,:three, other- young steers of the same ago and , same class, and brought from tho same outside district, were placed. .-.' . These throe outside animals all became affected, one having shown the first symptoms. of sickness -five months' after beiiig .placed on the "sick" country, another seven months, and the third ten months after. AH of these three animais are now dead of bush sickness, while the three grazing on the treated paddock are still in perfect health, and are growing and developing in a normal and natural manner, though they have been there over •thirteen months. Moreover, almost from the beginning o£ this experiment these three animals on the treated paddock did better, both as regards their growth and development and the putting-on of condition, than did the three on the untreated land even before' these began to show indications of bush sickness. -

(b) Three four-tooth ewes in lamb were, placed on a paddock'.'at Lichfield which had been ploughed and sown down, arid afterwards top-dressed; with a different dressing to that used in' the last-men-tioned experiment. At the same time five other four-tooth .ewes, also in lamb,- were placed on an adjoining grass / paddock with no top-dressing, the soil conditions being exactly similar. All the ewes lambed in due course. Now, two of the outside ewes and the whole of the lambs on the t untreated paddock are dead from bush sickness; of those on the treated paddock all the ewes aro healthy, as are two of the lambs. The third lamb lately died of bush sickness, but this lamb lasted out much longer than did the outside lambs. .It may be that a sfcond application of this soil dressing on'this paddock will put it right for keeping lambs healthy as well as sheep. In any case, all the lambs could have been got off as fat lambs before the one which died commenced to show any symptoms of sickness. . ■

_ Anotherexperiment with a 6imilar dressing was carried out in a bush paddock, two sheep and a young steer being placed <n it. Unfortunately, one of these sheep was killed by accident. The remaining sheep and the steer, .which have been on the paddock for 17 months, are still olive, healthy and doing well. (c) Two small paddocks in the bush were ploughed, manured, and sown down. Three young steers and ihree ewes were placed on these. The steers have now been on, the property for" 12 months, and aro in splendid health and line condition. , The ewes and their, lambs are healthy and in good condition. These animals wore on untreated land for about two months before going on the manured paddocks. They arrived on the property a year ago. Encouraging, but not Conclusitc. All the experimental animals were bred on, and were purchased from, country at a distanco far from the-area affected with bush sickness. Though these results are most encouraging, they cannot yet be considered finally conclusive Spring is the season , when trouble most frequently occurs, and I am anxious to see what happens to these animals when that period arrives. The knowledge so far gained, however, is sufficient to. justify au opinion that by the judicious treatment of the soil, tho slock can be kept in health for a niuch longer period than when tho land is not treated at all, and that with suitable soil dressings and good management, store stock can bo fattened and got into good marketable condition. In connection with tho investigntion, ono experiment carried out at the Walkceville Laboratory consisted of dosing two well-grown lambs with silica in the form of sodium silicate in solution. They have now received this daily for over four months, but-have remained in good health throughout. Further work is to l>o carried out on a larger scale, the ostablishment ol a small experimental nnd demonstration farm having been authorised by the Minister for Agriculture.