RESULTS OF EXPERIMENTS AGAINST THE CHICKEN MITE. 9 



Coal-tar oils were used in tests 12 to 18, inclusive. In tests 15 

 and 16 nest boxes were used and a dilution of 1 to 24 was efficient. 

 In tests with, chicken houses an emulsion of somewhat greater oil 

 content was only moderately efficient when diluted 1 to 12.3 parts 

 water. 



The material used in the last test was a powder containing 3.2 

 per cent oils and phenols and 1 per cent soap. It was diluted as 

 little as 2 pounds to a gallon of water. At this and all weaker 

 strengths it was inefficient. 



SUMMARY. 



Miscellaneous treatments. — Miscellaneous treatments for the chicken 

 mite included fumigating infested premises, banding roosts, using 

 a medicated roost, adding substances to the food and water of 

 fowls, placing prepared nest eggs under sitting hens, using medicated 

 nest hairs and nesting materials, hanging up substances in infested 

 premises, and treating hens with an ointment. 



Only two of these treatments were of any value. A medicated 

 roost remained free from mites, but the rest of the chicken house 

 continued infested. Naphthalene burned in sawdust and carbon 

 was efficient when used in a fumigatorium. Fumigation of chicken 

 houses does not appear to be satisfactory. In a chicken house of 

 average air-tightness, sulphur burned at the rate of 6 pounds to 

 1,000 cubic feet was inefficient. 



Dust. — Materials without value in the form of dusts were calcium 

 fluorid, sodium fluorid, sodium silico-fluorid, barium fluorid, barium 

 tetrasulphid, mercuric chlorid, Paris green, hellebore, refined and 

 commercial sulphur, and air-slaked lime. Used in tobacco dust, 

 nicotine up to 5.26 per cent was inefficient, and so also were phenols 

 up to 2 per cent in a dust carrier. Powdered derris root and pyre- 

 thrum flowers were efficient when undiluted. Naphthalene was effi- 

 cient only in the case of nest boxes and not in chicken houses. Tests 

 with powdered sabadilla seeds were insufficient. This material 

 gives promise of high efficiency. 



Paints. — Tests with materials applied as paints indicated that 

 heavy oils, either pure or slightly diluted with lighter oils, were 

 efficient. Cresol 5 and 10 per cent in a whitewash was of some 

 value. A stiff whitewash alone was inefficient, as was a preparation 

 containing 23 per cent naphthalene. 



It is not so easy to penetrate to deep cracks with a paint brush as 

 with a spray nozzle, and therefore painting houses with deep cracks is 

 not as effective as spraying. 



Sprays. — The following materials when applied as sprays to infested 

 premises were inefficient or without value: Ammonia water, 2.8 per 

 cent; ethyl alcohol; formaldehyde, 4 per cent; iron sulphate, 15.88 

 per cent; lime-sulphur (32° Baume), 1 to 9; sodium sulphur (12.45 

 per cent sodium sulphid and thiosulphate) , 1 to 5; sodium hypo- 

 chlorite, 0.94 per cent "available chlorine"; extract of derris root, 

 1 to 500. 



Nicotine solutions containing 0.07 per cent and 0.12 per cent free 

 nicotine, with the addition of whale-oil soap at the rate of 4 pounds 

 to 100 gallons, were of some value, especially the stronger solution. 

 Whale-oil soap at 1 pound to a gallon and at 2 pounds to a gallon was 

 also of some value. 



