336 CONTAGIOUS DISEASES. 



T'liberculosis of Birds {T liber culosis avium). — It is maintfiinecl 

 by some and contradicted by other writers that the tuberculosis 

 of birds differ in some essentials from that of mammals. Thus 

 Itivolta, Strauss, Mafucii, and other experimentalists have failed 

 to transmit the disease from mammals to birds, whilst Cadiot, 

 Albert, Nocard, and others state that the inoculation is 

 occasionally successful, and that the disease can be trans- 

 mitted from one to another ; and Nocard says : " It is true that 

 the lesions observed in the guinea-pig as the result of the 

 inoculation of Tuherculosis avium are widely different, namely, 

 large, red, and soft spleen, absence generally of tubercular 

 nodules in the lungs and liver, but the latter as well as the 

 spleen are crowded with tubercular follicles rich in bacilli, 

 and a few transmissions from guinea-pig to guinea-pig are all 

 that is necessary to enable these lesions to reproduce the type 

 so well described by Villemin." 



Lastly, the same writer says : " It must be remembered that 

 the tubercle bacillus so resistant to all causes of destruction ma}'', 

 however, experience profound modifications by means of suc- 

 cessive passages through the organs of divers species of animals. 

 But if the modifications which it undergoes as the result of 

 numerous transmissions through birds are profound enough to 

 make the bacillus of Tulcrculods avium a peculiar variety of the 

 bacillus of Koch, they are not enough, in my opinion, to make 

 these bacilli two distinct species." 



The avian bacillus is longer than that of mammals, grows 

 more rapidly and more readily on cultivation media, appearing 

 as thick, moist, luxuriant spots, which preserve their vitality 

 longer than those from man. They grow at a higher tempera- 

 ture — 109° F. — whilst those of the mammal cease to grow at 

 104° F. 



To prevent the spread of avian tuljerculosis it will be necessary 

 to kill all the birds in the infected yard ; the diseased ones being 

 cremated or buried deeply in the ground, their bodies surrounded 

 by a layer of some antiseptic, the healthy birds of course being 

 disposed of for food as quickly as possible. All the wood-work 

 of the hen-houses should be destroyed, the walls scraped and 

 whitewashed, the wash to contain carbolic acid, the excrement 

 removed and burnt with the wood- work, and on no account 

 should birds from an infected run be sold except for slaughter. 



