622 COMMUNICABLE DISEASES OF LABORATORY ANIMALS 



INFECTIONS WITH FILTERABLE VIRUSES 



Diseases due to filterable viruses have been reported by Petrie and O'Brien/ 

 Romer,^ De Gasperi and Sangiorgi,^ and Berge/ The outstanding feature of these 

 infections are nervous symptoms and paralysis. Quite recently Cole and Kuttner^ 

 proved that the peculiar acidophilic nuclear changes, which were noted by Jackson* 

 several years ago in the swollen epithelial cells of the salivary glands of 84 per cent of 

 full-grown guinea pigs, were produced by a filterable agent. Transmissions were in 

 part successful; the virus reproduced itself and could be preserved in glycerol for 

 twenty-eight days. The lesions which followed intracerebral injection of the infective 

 agent resembled those produced by Romer with his virus and the possibility that 

 it is identical with the Cole and Kuttner filter-passer should be borne in mind. 



DISEASES OF THE RABBIT 



Rabbits are generally considered unsatisfactory for experimental purposes owing 

 to their liability to a number of communicable diseases. In the laboratory or in the 

 rabbitry two infections and one ectoparasitic invasion — snuffles with its complica- 

 tions, coccidiosis and scabies — are probably the most troublesome and costly epi- 

 demic-producing maladies with which every worker becomes sooner or later ac- 

 quainted (Sustmann).^ Intestinal infections such as paratyphoid, pseudotuberculosis, 

 etc., are less frequent than in the guinea pig. Various other diseases (spontaneous 

 spirochetosis, encephalitis due to a protozoan parasite, a filterable virus infection, 

 etc.), which may invalidate experiments, have been recognized. The literature is ex- 

 tensive but scattered and confused.^ It is evident that multiple infections have fre- 

 quently not been identified, and the uncertainty regarding the etiological relation- 

 ship of various bacteria to some diseases persists even in the most recent literature. 

 Several excellent studies have no doubt clarified some of the disputed questions, but 

 even with the knowledge now available it would be unwise to compare the rabbit 

 epidemics of one country or even of one laboratory with those of another. It is desir- 

 able that in the future every outbreak be carefully investigated and the findings made 

 accessible for critical analysis. In order to facilitate such an undertaking, the essen- 

 tial facts concerning the communicable diseases of rabbits are set forth in the para- 

 graphs which follow. 



RESPIRATORY INFECTIONS 



Respiratory infections are most common among rabbits kept at commercial 

 rabbitries or at laboratories. As early as 1891 Beck,' and later Kurita,'" Kraus," Roger 



■ Petrie, G. F., and O'Brien, R. A.: loc. cit. 

 'Romer, P. H.: Deutsche med. Wchnschr., 57, 2685. 1910. 



3de Gasperi, F., and Sangiorgi, G.: Centralbl. f. Bakteriol., Orig. I, 71, 257. 1913. 

 ■» Berge, L. : Deutsche tierdrzll. Wchnschr., 32, no. 1924. 

 5 Cole, R., and Kuttner, G.: /. Exper. Med., 44, 855. 1926. 

 'Jackson, L.: /. Infect. Dis., 26, 347. 1920. 

 'Sustmann, H.: Deutsche tierarztl. Wchnschr., 29, 247. 192 1. 



'See Seifried, O. : "Die wichtigsten Krankheiten des Kaninchen," Ergehn. d. allg. Path. u. 

 Anat., Abt. I, 22, 432-589. 1927. 



9 Beck, M.: Ztsckr.f. Ilyg. u. Infektionskrankh., 15, 363. 1893. 



"'Kurita, S.: Centralbl. f. Bakteriol., 49, 508. 1909. 



" Kraus, R.: Ztschr.f. Hyg. u. Infektionskrankh., 24, 396. 1897. 



