CHAPTER XLV 

 COMMUNICABLE DISEASES OF LABORATORY ANIMALS 



K. F. MEYER 

 University of California 



Laboratory animals are frequently called "living test tubes" since they may serve 

 as "culture media" for the isolation of delicate micro-organisms and more often as 

 testing objects for the study of certain properties of bacteria and viruses (patho- 

 genicity, virulence, immunity reactions, pharmacological effect of metabolic products, 

 etc.). Though the importance of animals in bacteriological work is generally ad- 

 mitted, little or no attention is paid to this tool in the majority of the contemporary 

 textbooks. Lengthy dissertations deal with the physical and chemical prerequisites 

 of the test tubes or glassware in general. One may even find a few commentaries on 

 the methods of inoculating and bleeding certain species but nothing is said regarding 

 the breeding, the feeding, and the general care of the animals commonly employed. 

 Even the beginner should be familiar with the normal anatomy and physiology of 

 the guinea pig, rabbit, mouse, rat, pigeon, etc.^ Furthermore, the student and ad- 

 vanced worker should be reminded with unremitting insistence that for the successful 

 execution of an experiment of any sort the use of healthy animals preferably with a 

 known hereditary history is an absolute prerequisite. Poorly kept animals or those 

 which are already infected either with a latent or chronic disease may, aside from the 

 great losses entailed in the course of an experiment, furnish exceedingly unpleasant 

 surprises and many misleading observations. Irrespective of this fact, the whole sub- 

 ject is frequently dismissed with the statement that certain animals are often unsatis- 

 factory for experimental purposes owing to the liability to parasitic and intercurrent 

 maladies. 



The significance of the infections of laboratory animals has in the past received 

 relatively little attention on account of the hitherto separate flow of research in human 

 and animal diseases. Valuable observations have been reported in scientific and 

 technical journals, but unfortunately no comparative pathology of laboratory animals 

 has as yet been compiled. However, in recent years considerable interest has been 

 aroused by the recognition that some of the communicable diseases of laboratory 

 rodents furnish excellent material for the study of epidemiological problems, the 

 pathogenesis of certain infective agents, the protective mechanism which may follow 



' The following books or papers contain valuable information : Bensley, A. B. : Practical 4naton!y 

 of the Rabbit isded.). Philadelphia, 192 1; Donaldson, H. H.: The Rat (id ed.). Philadelphia: Wistar 

 Institute, 1924; Hunt, H. R. : A Laboratory Manual of the Anatomy of the Rat. New York, 1924; 

 Martin, P.: Lehrbuch d. Anatomie der Haussdiigeliere (2d ed.), 4i Lief. 3, 303-408. Stuttgart: Schick- 

 hardt & Ebner, 1922; Friedberger, E., and Schiff, F.: in Kraus and Uhlenhuth's Handbuch d. mikro- 

 biclogisch. Technik, 2, 1563. 1923; Raebiger, H.: Das Meerschweinchcn. Hannover: M. and H. 

 Schaper, 1923; Remlinger, P., and Bell, P.: Bull, de I'lnst. Pasteur, 22, 15-29. 1924; Ward, A. R., 

 and Gallagher, B. A.: Diseases of Domesticated Birds. New York, 1920. 



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