98 THE VITAMINES 



Among others, Funk and Cooper (277) showed in 1911 that the dis- 

 ease could be brought about with pure sugar, inulin, dextrin and 

 starch. The pigeon is quite the best animal to use in the study of 

 beriberi. When pigeons are placed upon a diet of polished rice, 

 they eat it with great avidity during the first few days. Following 

 this, their appetite diminishes markedly, and they frequently attempt 

 to disgorge the rice out of their crops. This behavior is more often 

 noticed in animals that are fed forcibly, but sometimes this rice is 

 again eaten voluntarily. This condition makes it difficulty to carry 

 out exact rice feeding experiments with pigeons. One has the impres- 

 sion that the animals have an aversion for rice, which, however, dis- 

 appears if the necessary vitamine is administered at the same time 

 with the food. After a few days, it is best to put the pigeon in a box 

 with a wooden cover so that its head extends; in this way it is possible 

 for one person to manage when forcible feeding must be resorted to. 

 The beak is opened and through a small metallic funnel with smooth 

 edges, the weighed rice is pushed into the crop with a glass rod. 

 Another method used by us was to prepare the food in the form of 

 pills, and feed them as such. For feeding purposes, it is best to use 

 healthy males weighing from 300 to 350 grams; 20 to 30 grams, of 

 rice per day may be given in three portions. If the crop should 

 happen to be full, it is necessary to wait till it is empty. We shall 

 speak of the effect of the food ingested when we come to the physi- 

 ology of vitamine B (p. 210). After several days of rice feeding, a 

 marked change is noted in the animals. Very little remains of the 

 usually predominating desire to quarrel when a number of pigeons 

 are kept in one cage. Likewise, the sexual instinct, such as the 

 strutting of the male around the female, seems to be held in abeyance, 

 and the animals sit on the perch in a sleepy, apathetic manner. They 

 experience increasing difficulty in flying on to the perch and a few 

 days later some of the pigeons sit on the bottom of the cage, regardless 

 of the fact that they are soiled by the feces of the animals on the 

 perch above. The fecal matter, normally of semi-solid consistency 

 and whitish color, becomes slimy and water-clear, or slight yellowish, 

 and the animals show no disposition to keep themselves clean. If 

 they are left to feed themselves, their appetite disappears gradually 

 and their condition is that of semi-starvation. About 30 per cent of 

 the animals which are permitted to feed themselves develop symp- 

 toms of beriberi, while the remainder die of general weakness. Of 



