56 LABORATORY MOUSE 



Linseed-oil meal 15 



Ground malted barley 10 



Wheat red-dog flour 22 



Dried skim milk 15 



Oat flour 15 



Yellow corn meal 20 



Steam bone meal ' 1 



Ground limestone 1 



Salt 1 



Total 100 



As mice are so dependent for health upon the constant 

 availability of food, it is advisable to have present in their 

 cages at all times a balanced-ration dog biscuit upon which 

 they may gnaw if other food has been consumed between 

 feeding hours. 



For mice to breed well, greens are desirable in the form 

 of lettuce or clover once or twice a week. Caution must be 

 observed in the feeding of lettuce that all tainted or rotten 

 spots be removed, for mice will eat these along with the 

 good portions and may be made sick by so doing. Hemp 

 seed is advised from time to time. According to fanciers, 

 animals suffering from lack of greens may become scurvied, 

 but this condition disappears when they are properly fed. 



A Closed Feeding Can. Mice delight in digging in an open 

 dish full of food. They waste great quantities of food by 

 kicking it out of the dish, and contaminate with their feces 

 that remaining in the dish. In order to eliminate these two 

 undesirable features of the open feeding dish a closed feeding 

 can has been recently devised and is in use at the Bussey 

 Institution (see Fig. 11). This consists of a half-pound coffee 

 can approximately 4 inches high and Sh inches in diameter. 

 In the side of the can is cut a 1-inch square hole, the lower 

 edge of which is h inch from the bottom of the can. The top 

 and sides of the hole are faced with a strip of tin projecting 

 \ inch into the can, to prevent the fall of food near the 

 entrance. A wedge-shaped cage made of galvanized-wire 

 cloth of \ inch mesh is soldered in place with the large open 

 end of the wedge over the entrance and projecting about 



