2i6 Veterinary Medicine. 



that few microbes or none were inserted, while the results came 

 mainly from the toxins or antitoxins. This would be entirely in 

 keeping with I^ignieres' observation that the blood and pulmo- 

 nary lesions often failed to furnish the pathogenic microbe, as 

 tested even by attempts at artificial cultures. The protection se- 

 cured from the antitoxins alone is short-lived, terminating with 

 the elimination of these elements, while that coming from the 

 action of the toxins on the leucocytes, and the stimulation by 

 these to the production of defensive products, is much more last- 

 ing and in ratio with the quantity of the stimulus introduced and 

 the profundity and duration of its influence on the leucocytes. 

 This may partly explain the occasional early exhaustion of the 

 immunity and the re-infection of the animal within a year after 

 inoculation. 



Physalix working in Chauveau's laboratory has found the best 

 results from the use of weakened artificial cultures. He culti- 

 vated the microbe of L,ignieres in peptonised bouillon having 6 

 per cent, of glycerine, and allowed successive cultures to rest 

 (without reseeding a new culture fluid) after they have attained 

 to their full growth. ' The strength of the culture is in inverse 

 ratio to the period that elapsed between .successive cultures, lead- 

 ing up to this one, and the first inoculation is made with the 

 weakest product that will produce a very limited local swelling 

 which is fully developed in 48 hours, and disappears in a few days. 

 Three or four inoculations are made successively with cultures of 

 gradually encreasing potency, after which immunity persists for 

 years. It is to be understood, that an overdose will overcome 

 the immunity at any time ; also that the passage of a culture of 

 lessened potency through a dog or Guinea pig will raise it to its 

 original virulence. Physalix operated only on young dogs, that 

 had not shed their milk teeth, and Injected 2 to 3 c.c. of the 

 culture as a dose with only 2.5 % mortality. Others had less success. 



Treatment. To secure good results in the treatment of dis- 

 temper every attention must be paid to good hygiene. An open 

 air life in summer, and a roomy, clean, well aired, warmed 

 building in winter are most important. Chills, foul air, and 

 filth generally are to be carefully guarded against. Food should 

 be moderate in amount, easily digested and nutritious. Milk is 

 especially good (sweet, skim or butter-milk) ; then biscuit and 



