404 TOKUYASU KUDO 



During the experiment the rats were kept each in a separate 

 cage with wire-net bottom. This allowed the feces and urine to 

 drop through. Both feces and food were carefully weighed. 



Acute thirst. Nine rats (eight included in table 1) were used 

 for the acute-thirst experiment. They were allowed dry food ad 

 libitum. The greatest difficulty in thirst experiments is to induce 

 the animals to eat dry food. If they refuse to eat, the result is 

 total inanition, instead of water inanition. The occurrence of 

 partial inanition (due to deficiency in vitamines or other necessary 

 dietetic elements) must also be avoided so far as possible. Vari- 

 ous methods of feeding in the acute-thirst experiments (table 1) 

 were used as follows : 



Group 1. Two rats (K 4.1, K 3.4) were fed with maize (Indian 

 corn) only, either whole grains or crushed, without water or milk. 

 They consumed an average of about 1 gram daily. The feces 

 averaged 2 to 2.7 grams daily. 



Group 2. Two rats (Sr, 8, Si. 1) were fed with dry biscuit ad. 

 libitum and 3 grams of milk daily. Each rat daily ate 2.5 grams 

 of biscuit and passed 2 grams of feces (average) . 



Group 3. Two rats (K 3.3, K 3.2) were fed with dry biscuit 

 and 5 grams of milk daily. They daily ate 2.9 grams of dry 

 biscuit and passed 0.8 gram of feces. 



Group 4. In this group, two rats (K 7.1 and Si. 3) in the 

 earlier days of the test were given (in addition to dry biscuit or 

 maize and biscuit) relatively greater amounts of milk (15 to 20 

 grams), which was gradually reduced in the later days to 2 to 

 2.5 grams. By this method the rat ate relatively more food and 

 continued active for a much longer period (killed after sixteen 

 to seventeen days). 



The daily average food intake for rat K 7.1 was 1.9 grams of 

 biscuit and 6.3 grams of milk. The feces averaged 2.7 grams daily. 

 For the other rat (Si. 3) the corresponding daily averages were 2 

 grams of biscuit and maize; 5.1 grams of milk; 0.4 gram of feces. 



In addition to the groups above mentioned, a male rat (Si. 2) 

 was kept alive without food or water (D ; total inanition) for eleven 

 days. This rat will be compared with those in the thirst series. 



