Sulphur │1 part │ mites, ticks. Kerosene │1 part │ Lard │2 parts │ ───────────────────────────┴──────────────────┴──────────────────────── NOTE.—By accepting that 1¼ teaspoonfuls made up to a pint with water gives approximately a 1% solution, any of the weak dilutions required by poultrymen can be easily prepared. _6. Disinfection_ [Illustration: FIG. 5.—HOW DISEASE IS SPREAD Germs of tuberculosis in the excrement of a fowl. (After Edwards.)] The important part played by micro-organisms in causing and spreading disease must be understood before the value of disinfection can be fully appreciated. The poultryman must develop a sense of sight that sees lurking microbes at every turn, especially in unclean corners. Figure 5 shows germs revealed by the microscope in the excrement of a bird suffering from tuberculosis. The fact that this speck contained so many germs, although it was far too small to be seen with the naked eye, will give an idea of how epidemics may be caused by food, water, and soil contaminated by excreta, nasal discharges, etc. Regular and thorough disinfection of woodwork, of feeding vessels, and of the drinking water should form part of the routine of poultry management, and a stock of disinfectants should always be kept on hand. It will be found convenient to have an iron drum with a tap for a diluted solution, say 5%, of some standard disinfectant—e. g., creolin—that can be further diluted as required. _Water._ A stock solution of permanganate of potash, made by adding ten grains to one quart of water, should always be kept on hand for purposes of disinfection. When there is danger of infection, two tablespoonfuls of this solution should be added to every gallon of drinking water. _Feeding Vessels._ Clean with boiling water. [Illustration: FIG. 6.—AIDS TO THOROUGH DISINFECTION] _Houses and Fixtures._ Spray with 2% to 5% creolin (or other disinfectant) and whitewash afterwards, or use whitewash to which 2% of creolin has been added. The whitewash should be prepared with quick-lime. The house should first be cleaned out with an iron scraper and scrubbing brush, using a liberal supply of water (see Fig. 6). _Soil._ The most convenient of the following methods should be adopted: (1) Spray surface with 5% creolin. (2) Spread straw over ground and set fire to it. (3) Fork over and lime. This method is not sufficient if serious contamination is suspected. CHAPTER II SUMMARY OF EXTERNAL SYMPTOMS AND TREATMENT