VACCINATION. IMMUNIZATION. INOCULATION 263 



The local reaction consists of an infiltration at the site of injection, form- 

 ing a large, abrupt, painful swelling with radiating lymphatics appearing as 

 raised cords, generally attaining greatest prominence at from 18 to 21 hours 

 after injection. The general reaction is exhibited by a stiffened gait, depres- 

 sion, loss of appetite, and accelerated breathing. 



3. The presence of a local reaction, especially when associated with a 

 general reaction, should be regarded as evidence of glanders, even if the 

 thermal reaction be sUght or absent. 



4. Animals giving an atjrpical reaction and those reaching a maximum 

 temperature of 103° F. should be retested after the expiration of not less than 

 15 days.) 



(c) Cutaneous malleinization consists of the injection of mallein 

 into the scarified skin and the pronounced local swelling which is 

 produced. The method is complicated, technically difficult and 

 the reaction varies with the method of application (superficial or 

 deep scarification). 



Directions for Applying the Mallein Eye Test. 



I. Nature of the Test. — Horses infected with glanders are hypersensitive 

 to mallein. They therefore react when mallein is instilled into the conjunc- 

 tival sac with specific local symptoms of inflammation. The specific reaction 

 is a pronounced redness and swelling and a purulent inflammation of the 

 conjunctiva of the eyelids, especially in the inner canthus of the eye (drops 

 of pus, flakes of pus in the discharge, purulent discharge). A serous, sero- 

 mucous or mucous discharge is not specific. The specific reaction does not 

 begin immediately, but at the earliest 5 to 6 hours after the instillation of the 

 maUein; it usually continues for 36 to 48 hours, sometimes longer. The best 

 time to observe it is from the twelfth to the twenty-fourth hour. The sUght 

 symptoms of irritation of the conjunctiva (tears, photophobia, shght redness 

 of the conjimctiva), which occur in many horses very soon after the mallein 

 is instilled and disappear after a few hours, must not be mistaken for the 

 specific mallein reaction. 



II. Application. — ^Either fluid mallem (raw mallein) or dry [precipitatedl 

 mallein is used. 



With a brush or dropper (eye pipette), a few drops of fluid, undiluted 

 mallein or of a freshly-prepared 1 per cent, solution of dry [precipitated] mallein 

 in distilled water or physiological salt solution are introduced into the right 

 eye. The left eye serves as a control. 



In order that the eye may be examined for the symptoms of the specific 

 reaction in daylight, it is recommended that the test be begun in the morning 



