CARE OF CAPTIVE ANIMALS — WALKER 337 



Struggling with an animal to control it while giving it medical or 

 surgical treatment often does more harm than can be offset by the 

 treatment. If treatment is essential, care and strategy should be 

 used. Animals can be rendered sluggish by giving certain drugs in 

 their drinking water. Small creatures can be anesthetized in closed 

 containers. Medicine can often be given in food without arousing 

 the animal's suspicions. 



The size of the dose of medicine should in general be proportionate 

 to the size and weight of the animal; that is, a small animal should 

 be given a small dose, and a large animal a large dose. 



So-called cage paralysis probably has numerous causes. Inactivity 

 has been mentioned. Rickets is another frequent cause. Proper 

 food, sufficient sunlight, and in some cases supplementary feeding of 

 ricket-preventing medicines and foods will go far toward obviating 

 this condition. 



Occasionally some mammals lose their hair gradually or fairly rap- 

 idly and do not grow new coats. A corresponding condition some- 

 times exists in birds. The cause of this loss of hair and feathers is 

 not definitely known, but in some instances it is caused by deficiency 

 in diets, though just what dietary measures can be used to prevent it 

 is, in the majority of cases, still uncertain. 



Some birds, particularly parrots, develop the habit of plucking 

 their own feathers and eating them, or plucking the feathers of their 

 cage mates. Apparently this indicates a dietary deficiency, which 

 has been remedied in some cases by giving salt, fat, bones, and meat. 

 On other occasions such methods have been without beneficial effect. 



The incisor teeth of rodents in captivity are often found to be so 

 long the animal cannot eat. In such cases, it is necessary to cut the 

 overgrown teeth to a proper length. These teeth grow continuously 

 throughout the life of the animal, and the animal will usually keep 

 them worn down if it has plenty of wood, nuts, or other hard mate- 

 rials to gnaw. If one of these chiseling teeth is broken, the opposing 

 tooth must usually be cut at frequent intervals. 



If animals are kept on cement floors without earth or other mate- 

 rial over them, careful watch should be kept for corns on the soles of 

 the feet, or actual wearing away of the skin and flesh to the bone. 

 (See pL 8, fig. 2.) 



Toenails must sometimes be trimmed. 



It is often desirable to render flying birds flightless so that they 

 can be kept on lawns or in large enclosures without wire covers. Here- 

 tofore this has generally been accomplished by amputating the ter- 

 minal joint of one of the wings. This is a more or less brutal and 

 disfiguring method. Another method — eutting one of the flight ten- 

 dons — which causes little pain and does not disfigure the bird, was 



