A Preliminary Note upon the Intra-Dermal-Palpebral Method of Mallein Testing for Glanders

A Preliminary Note upon the Intra-Dermal-Palpebral Method of Mallein Testing for Glanders

355 ~elleral Brticles. A PRELIMIK AR Y NOTE UPOK THE I~TRA-DERMAL­ PALPEBRAL METHOD OF MALLEIX TESTIXG FOR GLANDERS. By the courtesy of the French m...

1MB Sizes 0 Downloads 12 Views

355 ~elleral

Brticles.

A PRELIMIK AR Y NOTE UPOK THE I~TRA-DERMAL­ PALPEBRAL METHOD OF MALLEIX TESTIXG FOR GLANDERS. By the courtesy of the French milita ry a uthorities, on July 9 a very interes tin g demon stration of the value of the above method of testing with mallein was g iven by Professor Douville (of the Lyons Veterinary School, now se r vin g as a lieutenant in the French Army), in the pre sence of BrigadierGeneral Moore, Colonels Butler and Newsome, Ma jors O lver, O'Rourke , and Wadley, Lieutenant Hobday, and a number of other ve terinary offic·e rs. The results were so convincing, and this demonstration was so skilfully carried out, that it was at once decided t o give the method a thorough tri a l in the British Service. This method of te stin g with ma ll ein has been for some time on tria l in the French Army, and the re sul ts have been reported upon most favourably, so much so that, under war conditi ons, at any rate, it is pr·obable that it will supp lant the subcutaneo us method almost ·entirely. The chief advantages claimed for it are that the dosage is very much le ss, thus saving mallein , and necessitating less materia l to be carried or sent about the country (a very great asset whe're thousands of horses have to be te sted); secondly, the reacti on is so prono unced that a decisive opinion can be given with much more confidence than one is able to sometimes do by the subcutaneo u s method; thirdly, there is no need whatever to take any temperature s, and the test can be carried out on fever ish animals and in any surroundings. An ·ord inary small I g rm. yringe (Pravaz or other pattern), with screw piston graduated to l u c.c ., is used, and the needle should only be abo ut ~ 111. in length . Of mallein , as at present supplied for the Briti sh Army Service, in stead of a do sage of I c.c. only 2 minims are nece ssary. In the French Army ma ll ein is obtained from the Pasteur In stitute. and a special concentration of I to 3 (malle ine dilu ee au quatrieme pour intra-dermo-reaction) is prepared .

The

FIG. I.



Veterinary:1 ollnla!.

Side view showing the reaction after injection into the lower lid of a glandered horse.

FIG. 2.

Front view of a " reactor." Note the muco·purulent discharge from the inner canthus.

The injection is made into the skin of the eyelid, the lower for preference, although either will do. In the majority of horses the head is merely held by an assistant; or, if the animal is at all re stless, a twitch may be applied. The operator, standing by the cheek, with the syringe in the right hand, carefully inserts the needle parallel to the eyelid into the layers of the dermis itself, and not subcutaneously (although no harm results, even if it does penetrate into the subcutaneous tissue), holding a fold of the eyelid between the finger and thumb ()f the other hand . The piston, the dose having been previously grad uated by the screw upon it, is then pressed and the dose inserted. The result is as follows:In healthy animals the eyelid remains unchanged, or becomes only very slightly swollen between the second and sixth hours, this swelling disappearing about the twelfth hour. In a glandered horse there is a very characteristic reaction. This takes the form of severe and extremely sensit ive cedema of the eyelid, accompanied by a more or less profuse mucous discharge, the conjunctiva being bloodshot and the eye more or less closed.

Method of Mallein Testz"ng for Glanders

FIG. 3. A typical reaction (lower lid injection).

If the horse has previously had a subcutaneous mallein test, a delay of twenty days should elapse before resorting to the intradermal method. Out of between 5,000 and 6,000 mallein tests made during the past eight months the intradermal test never failed, all reactors being proved on post-mortem to be glandered. In almost -e very case there was agreement in result between the palpebral and the subcutaneo us methods, but 111 a few instances animals were met with

357

The reaction is readily visible about the ninth or tenth hour afte;' the injection, and is at its heig ht between the twenty-fourth and thirty-sixth hours, remaining sometimes for three or four days. In the 'e vent of a doubtful or 111complete result, an injection of 2 minims into the other eyelid may be given forty-eight hours later. The swellin g will persist in a glandered horse for thr-ee or f.our days and then gradually disappear. Hypodermic injections 111 the usual site in the neck can, if the operator wishes, be done at the same time as the injection into the eyelid, and in a glandered horse each will act equally well.

FIG. 4. A typical reaction (upper lid injection).

T he Veterinary Jou rnal. which reacted definitely to the intra-dermal-palpebral te st , but in \\'hich the hypodermic te st in the neck wa s indecisive. In all cases the post-m ortem examination proved the diag no si base d upon the intra-dermal reaction to be accurate .

ON THE EMPLOYME NT OF POLYVALENT SERUM IN VETERIKARY MEDICINE. By

MON SIEUR

L. CUVILLI ER .

A /fort Vcterilla1Y School, Paris. EVERY time that a micicobe penetrates a point of the body it produc·es a defensive reaction ipterpreted by an afflux of leuc ocytes, which, passing out of the vesse ls by diaped-esis, move in great numbers to meet the invading element. Diapedesis is followed in the great majority of cases by phagocytosis of the germs which are for the most part surr-ounded by white cells . From then the se suffer a very varied fate, according to the pathogenic value and the toxicity of the microbian ag ents which they have in g ested; if the digestion of the atox ic or little virulent bacteria is effected normally, that of the pathogenic and toxic microbes is un reali zable, and the leucocyte does not delay at all t o succumb to the action of the g erm. White cell s thus de stroyed are lo st for org anic defence , for regenerati·on of the ti ssues; they constitute the fig u rative fundamental -e lement of pus. Anti septic medication, so largely us-e d to-day, propo ses t o de stroy on fhe surface of infected wounds and muoosa:! the organi sms that multiply there. To thi s end it uses different chemical or physical ag ents, which all proceed by oxidation of bacterian protoplasm or by coa g ul ation -o f thi s substance. But for tho se who know the very real re sista nce of bacterial protoplasm to different agents, it appear s beyo nd di spute that before reaching the microbian dement the anti se ptic ex ercises its acti-on violently on the cells of the wound con cerned , a nd notably on t hose very youn g and fra g ile element s whi ch co-operate in its repair , and vi olently also on the leuc ocytes who se chem iotax is has been a long time establ ished.