PREVENTIVE MEDICINE 243 



tubercle bacilli, they are sometimes found to exhibit lesions due to 

 human tubercle bacilli. One must, therefore, assume that such 

 have been infected from phthisical persons. The possibility of 

 such parrots reinfecting man must of course be borne in mind. 

 That it may be a common disease amongst parrots is shown 

 by the fact that of 700 birds examined by Frohner* between 1881 

 and 1894 no less than 24-3 per cent, were tuberculous. 



PREVENTIVE MEASURES to be effective must be thorough. All 

 the birds should be killed off, as the salvage of one or two favourites 

 will probably mean reinfection of the ground and of any fresh stock. 

 Poultry houses must be thoroughly disinfected, and after a pre- 

 liminary cleansing the free use of the painter's lamp on all wood- 

 work is to be strongly advocated. Houses and pens should be 

 shifted to fresh ground, and the soil whereon they stood dug up 

 and disinfected by mixing therewith an abundance of quicklime. 

 Fresh birds should not be introduced unless and until the ground 

 has been cleansed as well as may be and left vacant for some weeks. 



OVINE TUBERCULOSIS. 



Tuberculosis in the sheep is very uncommon. Ostertagf has 

 noted several cases in Germany, and one or two instances of a 

 natural infection in this country have been described by M'Fadyean. 

 The sheep is easily infected experimentally with tuberculosis, and 

 its rarity in this species is undoubtedly due to the out-door life 

 which sheep live. It is rather difficult to understand why cases are 

 not at times seen amongst lambs when one takes into consideration 

 the fact that they are frequently reared on cows' milk, which, 

 though warmed, is not as a rule sterilized. Special preventive 

 measures do not seem to be called for. 



CANINE AND FELINE TUBERCULOSIS. 



The disease is not infrequently met with in dogs and cats, and 

 is more often seen in large cities, in fact it is very common in town 

 cats. Infection may occur either by ingestion or by inhalation, 

 chiefly by the former. Cows' milk and butchers' offals are often 

 sources of infection, but Gray considers that the disease is usually 

 contracted from man. Animals must be considered to be danger- 

 ous owing to the possibility of infecting persons with whom they 

 come in contact. Dogs, and particularly adult dogs, are highly 



* Hutyra and Marek, Spec. Path., Vol. I., p. 615. 



\Journ. Comp. Path., 1891, Vol. IV., p. 361, Abs. 



