588 PHYSIOLOGICAL CHEMISTRY 



Figure 179 shows the individual parts of cages and Fig. 180 the assembled 

 cage. 1 Animals should be kept in a room with a fairly constant 

 temperature (65 to yoF.) and not exposed to direct sunlight. Rats 

 with young should be furnished with strips of paper for nesting. 2 

 Stock animals are fed a mixed diet of ordinary foods or dog biscuit 3 



FIG. 177. GUINEA PIG WITH SCURVY. SHOWING "SCURVY POSITION. 

 (Hawk, Smith and Bergeim: Unpublished data.) 



, cup holders, cups, and other accessories may be obtained from the A. B. Hen- 

 dryx Company or the Herpich Company, both of New Haven, Connecticut. These 

 cages are 9 inches in diameter, 8 inches high, made of Y inch mesh galvanized wire netting, 

 and bound at the edge with sheet zinc. The cage has no bottom but is set in an ordinary 

 enamel-ware pan with sides 2% inches high and about gYz inches in diameter at the bottom. 

 Sides of pans should flare enough, so that they may be stocked for storage. Food con- 

 tainers are porcelain cups 2% inches in diameter and i% inches high, such as attached 

 to bird cages. Water holders are 2 oz. bar glasses. Five or six sheets of paper napkin are 

 placed in bottom of pan to absorb urine and distilled water. The paper is covered with 

 2 discs of ^ inch mesh wire netting. The cup holder with cups is hooked over the edge 

 of the pan and rests on the wire disc. Entire cage can be lifted to remove rats or introduce 

 food. To clean, cages may be rinsed with water and sterilized with steam. Cages should 

 be cleaned at least once a week. All parts of cages should be interchangeable. Bedding 

 is not necessary except for rats with young, if a proper temperature is maintained. 



2 Stock animals are better kept in rectangular cages 18 inches long 12 inches wide, and 

 9 inches high, front and sides of ^ inch netting, reinforced with zinc; back and top of 

 sheet zinc, top being hinged and fastened with a small brass catch in front. The bottom 

 is heavy netting of one inch mesh. The cage rests in a galvanized pan 18^ X 12% X i 

 inch. The bottom of the pan is covered with one or two sheets of thin blotting paper, held 

 in place by ^ inch mesh wire netting. This netting can easily be removed and cleaned. 

 Water cups like those used in parrot cages may be slipped through an opening in the front 

 of the cage. Bedding is not used. A cage is ordinarily used for 4 rats. See Fig. 181. 



Just before or after a litter of young is born, the mother is best removed to a special 

 cage 9 inches square and 9 inches high, like the other cages but have no (see Fig. 182) 

 bottom, as very young rats may be crushed against the heavy netting. The separate sheet 

 of fine netting mentioned above is used. Crepe paper strips from the Dennison Company 

 may be used 'for bedding. A special glass tube may be used for water. When the 

 young are three weeks old, they are transferred to a larger cage and the mother left with 

 them until they are at least 4 weeks old. 



3 A suitable biscuit may be obtained from the Potter & Wrightington Company, Charles 

 River Avenue, Boston. 



