210 Diseases of Poultry 



biting and digging of the claws of the lice may cause sores 

 and the nervous irritation and loss of sleep may cause general 

 debility and bowel trouble. Little chickens are very sus- 

 ceptible and often die. Lice are frequently found in large 

 numbers on birds suffering from roup, gapes, etc. In some 

 cases their presence has rendered the birds more susceptible 

 to other disease, while in others it is probable that the birds 

 lack sufficient energy to dust themselves. 



The sure test for the presence of lice is, of course, finding 

 the lice. Part the feathers under the wing, on the back 

 and around the vent and examine the exposed skin. Exam- 

 ine the head and neck feathers and look between the large 

 feathers of the wing. When present the parasites are easily 

 found by any one who is familiar with them. It seems in- 

 credible that serious infestations can escape the eye of any 

 poultryman. 



Treatment. — Sanitary surroundings and liberal range 

 help the birds in their attempts to keep themselves free from 

 lice. The dust bath is very efficient in holding the pests 

 in check. It is doubtful, however, whether the dust boxes 

 which used to be almost universally kept in the poultry 

 house are of any real value. It is a noticeable fact that 

 dust boxes are much less used now than formerly. As com- 

 monly made these boxes are too small, and too shallow, and 

 are not filled with the proper kind of material. Hens will 

 use them, in most cases, only as a last resort if at all. 



When possible, birds should be given access to dry, sandy 

 ground, and they will provide their own dust bath. Some 

 authors advise adding insect powder to the earth in dust 

 boxes for bad infestations. It is doubtful whether under the 

 best of circumstances this does anything but waste the 

 insect powder. It is better to apply the powder directly 

 to the bird and furnish clean earth for the dust bath. 



When hens are used for incubating and brooding it is 



