TUBERCULIN TESTING OF CATTLE.

Otago Witness, Issue 2285, 16 December 1897, Page 38

TUBERCULIN TESTING OF CATTLE.

The accumulation of proof .concerning (he infection of human beings with tuberculosis, or consumption, by means of the milk »nd meabof battle suffering from the disease has contfcntined the health authorities in all well-ordered communities to comiderand promote measures for the protection of consumers. Haviog acquired fairly exact knowledge how diseases may be propagated and spread by the consumption of contaminated food, health authorities of any repute now act on the rational axiom that "he who cures may be the cleverer, but he who pre- ! vents dif-esso is the safer physician," and in innumerable instances have devised mean* of preventing cimrnuDicablo disease through food channel?. Of these precautionary measures the frequent inspection of dairy herds and condemnation of aninnta therein that react to the tuberculin tea, in order to prevent the distribution and utilisation of infective milk are rightly regatded as indispensable, because tuberculous matter in milk is exceptionally active in its operation upon animals fed either with the milk or with the dairy produce derived from it. Nex*i in importance is the establishment of public abattoir?, and their management under such precise and systematic supervision as WouM prevent the sale to th 9 public of meat contaminated with tubercle, it being distinctly understo ><3, however, 'tbat meat of cat-be only slightly affected with tuberculosis is nob to be condemned, tbe disorder in such cases being usually confined to the organs removed in the process of dressing. In considering the problem of the practical and practicable means of eradicating thi* insidious disorder from the cattle stock of the colony, consumers of beef and cattle-owners alike may place implicit confidence in tho Codings of the Royal Commission on tuberculosis— corroborated as they are by the Health departments in the principal cities of Europe and America — to the effect that " tuberculosis of tho animal is chiefly a disease of organs which, are for the most part removed ia the process of dressing, and therefore they sea no obj> ciion to the sale of meat substance from carcases which have shown only localised tuberculosi-, aud from which every particle of tubercle has been skilfully removed." In this oonnection i!s must be explained that experts in their evidence before tho commission classified tho attacks ai "mild tubercolius," " moderate tuberculosis," and " generalised tuberculosi?." Caitla in tho l»st ! stage of the disease are universally known as " pinere," and it is one of the mysteries of farm- ! ing that such animals should be kept unproGtably alive until tho disorder has co developed as to permeate tha whole of the organisms. When the disorder cxisfss in the "mild" and " moderate " form?, the cattle affected are to [ all appearance healthy, and so tnay are in degree, for they will milk or fatten satisfactorily enough, vet the milkers should have no place in I a dairy herd. But, until lately, the recognition of tuVerculosia in its early stages was virtually impracticable, and it was not until tbe special value of tubwculia as an *id to diagnosis became generally recognised that tho existence of the disease or freedom from it in an apparently healthy herd could be conclusively determined. Now, so universally has the agency of the specific for purposes of diagnosis been recognised, that cattle-ownera everywhere ara availing themselves of the boon, and tuberculin, for some years a common article of commerce on the Continent of Europe, and more recntly in Great Britain, is certain to come into demand in this colony wheu all the advantages resulting from it* usa have been made plain to owners of stock. It ought to have been more generally known than was the case on the occasion of the Otago Society's agricultural show that the young ' cattle exhibited by the New Zealand and Australian Land Company Jbad been subjected to the tuberculin test and had not reacted. On making inquiry tbe information was elicited that tho purebred cattle of different breeds had been tested by an expert, any animal reaoting being withdrawn from th© breeding section and turned out for other use. In the future, therefore, naoab assuredly purebred animals for breeding purposes offered for sale by the company will deservedly command higher prices because of the guarantee of constitutional soundness than other equally well-bred stock not bo accredited. In New South Wales dairymen especially are thoroughly convinced that tuberculin will detect the presence of tuberculosis. The Veteciuwy Department place at the disposal of cattle-owners the means for deciding as to the health of their herds. A representative of the Sydney Mail having ascertained that Mr Stanley, chief veterinary officer in the Health department, was about to test with tuberculin a herd at request of the owner, made application and was permitted to report the particulars. Tho Mail quotes Mr Stanley's instructions in regard to the test as follows :—: — Koch's tuberculin is a light-brown fluid with a faint smell, and is simply a glycerine extract of pure cultivations of tbe tubercle bacilltH, filtered through porcelain, and thereby it is absolutely free from the disease germs, so that there is no risk whatever of conveying tuberculosis by injecting this fluid into either mankind or other animals.' Tbe tuberculin is sold in small sealed bottles containing sufficient to inject five cattle, or in larger quantities, from Dr Koch's laboratory in Germany. It keeps well, but if contaminated by exposure it then becomes turbid and is useless. It is used t»s a purely scientific method of determining tbe existence of the disease by measuring ; the reactions caused l>y its injection as shown by the temperature of the animal at given periods afterthe inoculation. The cow to be tested should have the body tern perature taken and recorded by inserting a clinical thermometer into the rectum or vagina and retaining it there for at least four minutes. Do this about 10 hours before and again at the time of inoculation. It should rrgister lOOdeg to 102desr, that being the usual normal temperature of the ; animal. The evening record is usually a few DOints higher than in the mornioff, and is the

most convenient time for inoculating. Tbe opera*, tion is dona with an ordinary subcutaneous in« f jection syringe, graduated ioto minims, or Into cubic centimetres. Tho dose is from ftvo minims of the tuberculin. The hair should bo clipped off an inch or so of skin behind tha shoulder. The skin may be washed with some disinfectant, then the needle is thriwt through the skiu and downwards ju3fc uivier it, mul tho piston pressed to eject the fluid; then carefully withdraw the •needle. The tuberculin will permeate the whole bod/,"and if the cow is tuberculous it will in a few hours cause a mild favor. This is iUcerUined by xising tbe thermometer, say, about 12 hours after tho inoculation, and repeat the observations evsiy three or four hour*. The register will rise fram ldeg t j 3deg above tho normal record of health. Tbo fever is at its height in about 20 hours after the injection, then "gradually subside! and dwap* pears altogether. If (be animal ia free from tuborculosis, then the temperature of the body remains uealtered throughout tha whole time, merely rising or falling » few points, duo to natural Burroundiogs A rise of ldog only is suspicious! but' not' decidedly definite, but fiom 3deg is considered diagnostic of tha oxistence of tuberculosis. In case of a doubtful reaction the aarual can be treated a3 a suspect, and re-tested a few months later. The particulars of the testing of the herd in question aro minutely stated ia tho Mail. The temperatures of the animals suspected were taken and recorJed, and then tho injecting was proceeded with. Mr Stanley, standing ou the near side of tbe beast, clipped off tho hair from an inch square behind the shoulder, near the crop. Ha cexb with, a em«ll curved li\nce!i r . made a nick about half an inch in length through - the skin. The cai>M« flinched so when nicked . with the-lancet as to justify Mr Stat-luy's remark ' that to save the breakage of the injaoting needle J it ii well to first use the Unoafc. The needle," which i 3 abaub Hiu long, is pushed right down just beneath the skin, and the tuberculin (five miuims) is injected speedily. I a tko" boats described in this instance the quantity of fluid injected was 10 minimi, because five minims of glycerine and water had been added to tho five minims of tuberculin. This lessens th« ohance of waslo, and when non-professional men do the work Mr Stanley suggests that the five minimi ' of tuberculin shall ba mixed with 15 mi trims of the innocuous fluid. TFaen tbe injections were all finished, the eittle wore pUcod a b grass until ' 6 o'clock rtexb morning, when they wera placed in ihe bails and their temperatures b»kau and entered ou a chart supplied by tha Board of Hea'lk Twelve hours of the tuberculin's influence produced' but veryliltlj change. Tha Ayrshire bull, which had bs*n before the injection 101 9, was in the morning 1021. All tha fun tie* were close ,to 102, bnb the savea-yeac-old bull,- which was 14 hours before 102 8; was 104*8. Thr^e hours afterwards, wheu temperature was again t»k- n, he was 105 1, and ab noon he was still 105'lrg, aud declared tuberculous. He w«s a well-fleshed, healthy-looking bull,'and, in fact, cost £45 when he w»> brought to tho farm five yeaws before. With the owner** willing consent he was killed, and the postmortem work very speedily done. As soon is tho throat was opened- three great tnbarcules, one of which was the six of a big potato, wera di-c'o cd. Further investigation disclosed tubercles »ll along the viscera and on tba lungs. In facb it;" was a 'bad cafe of tuberculosis, although in life the animal had shown no w«,st-, iug, no chronic cough, no diarrhea*. It is extremely probable thai funnsrs ia this colony will be found. unwilling to sabmtb theircattle to tke tuberculin tt»t publicly, although • doubtless before long ib will be-eompahtary-irf < dairy herds. The above description of Mr '■ Stanley's proceedings shawa bhe simplicity of , the operation, and ib may fairly be assumed ' thab wero supplies of tuberculin aad injecting needles procurable ab moderate rafce* the majority of catble-owners would, for their own satisfaction, carry out th.3 testi. \