Cnapter 13 



CARE AND RECORDING 



i^v John J. Bittner, Roscoc B. Jackson Memorial Laboratory. 



The salient features in the care of mice are probably similar in most 

 laboratories. The majority of investigators naturally consider that the 

 methods they use are superior to those employed by others. In some 

 respects they may be correct as the system one must apply is often deter- 

 mined by unusual circumstances which only experience may correct. A 

 stock of mice maintained in a satisfactory condition by one worker may die 

 out under the care of a second with conditions practically identical. There 

 is also in the management of mice some indescribable "knack" which some 

 have and others apparently lack. There is no indication that this is due to a 

 lack of interest on the part of the latter individual; it is more likely to result 

 from too much attention and handling of the animals. 



The method to be described for the care of mice is that followed at the 

 Jackson Laboratory with satisfactory results. 



The mouse boxes (Fig. 171) are made of wood and measure 12" X 12" X 

 6". The bottom is covered by I4" plywood. The front, back and sides of 

 the box are made from ^ 2" stock and the center partition is -^4" thick. The 

 thick center partition gives more room for the covers to overlap and the life 

 of the box is lengthened as it is through this board which the mice are most 

 likely to gnaw. The boxes may be painted or may be dipped in a solution 

 of equal parts of turpentine and linseed oil containing dryer. Lionoil may 

 be substituted for the linseed oil. 



Wooden boxes have some advantages over metal or wire cages, the most 

 important being that the mice are warmer than they would be in metal boxes 

 and are not subjected to drafts. Also, less light penetrates the boxes thus 

 giving a more natural habitat for the rearing of young. The initial cost is 

 considerably lower than for the other types, but replacement must be made 

 more often. 



The stock for the covers measures 1I4" X f^" with the pieces cut so that 

 part fits down into the box and the flange overlaps the side of the box to 

 support the weight of the cover, the food hopper and the water bottle. The 



475 



