2 BULLETIN 888, U. S. DEPARTMENT OF AGRICULTURE. 



CHICKEN LICE. 



Several species of lice were present on the fowls used in these 

 tests, viz, the body louse, Menopon liseriatum Piaget; the shaft 

 louse, Menopon pallidum Nitzsch; and the large hen louse, Gonio- 

 cotes abdominalis Piaget. The most abundant species were the body 

 louse and the shaft louse and these were always present in large 

 numbers. 



METHODS OF TESTING. 



Three general methods of testing were employed: First, treating 

 the individual fowls by dusting, spraying, dipping, or the "vent 

 treatment" (see Mercurial ointment, p. 4-5); second, fumigation by 

 confining the fowls in a box which had been painted or sprayed inside 

 with the material to be tested; and, third, painting or spraying the 

 roosts and dropping boards or the whole interior of the house. 



Dusting. — Two persons worked together in dusting, one holding 

 the bird and spreading the feathers, while the other applied the powder 

 with a shaker or small hand dust gun. Except where noted the pow- 

 ders were well rubbed into the feathers. 



Spraying. — The liquids were applied with a hand sprayer and 

 were also well rubbed in, unless otherwise noted. 



Dipping. — In the dipping tests the birds were held in the solution 

 for from one-half to one minute and the head was submerged for 

 about a second, once or twice. 



Vent treatment. — In these tests the materials were thoroughly 

 rubbed into the skin of the fowl around, or just below, the vent. 



Fumigation. — In these tests the liquids, largely hydrocarbon oil 

 mixtures, were applied to the bottom or bottom and sides of a box 

 and the infested fowls were then placed in the box, which was cov- 

 ered with two or three thicknesses of burlap. The birds were left in 

 the box for from 5 rninutes to 3 hours. 



Painting the house. — For these experiments the roosts and dropping 

 boards, and often the whole interior of the chicken house, were painted 

 or sprayed a short time before the birds went to roost, and the house 

 remained tightly closed for that night. 



OIL PREPARATIONS USED AS SPRAYS. 



Tests with 22 different mixtures containing hydrocarbon oils, 

 phenols, nitrobenzol, coal tar, wood-tar distillate, pyridine bases, 

 and soaps showed that such preparations will kill practically all of the 

 lice if lightly applied. The emulsions at dilutions not greater than 

 1 to 100 are also effective, but a dilution of 1 to 250 is of no value. 

 Dipping tests indicated that these preparations are effective at about 

 the same dilution. When dipped in or rubbed with the undiluted oils 

 the fowls as well as the lice were killed. In two tests fowls dipped 



