Disease prevention is much simpler and cheaper than control or cure. Medicines are only emergency measures used in an attempt to overcome disease. _a._ SANITATION. This is the most important way of preventing disease and its value should never be underestimated. The following rules for sanitation in the care of pigeons must be strictly adhered to: (1) Keep loft clean and dry. (2) Keep drinking fountain clean and water free from pollution. (3) Quarantine new stock until certain that all birds are free from disease. (4) Never permit stray pigeons, wild birds, or rodents (mice, rats, etc.) to enter the loft. (5) Never feed pigeons on a dirty floor, because most of the more serious diseases are transmitted through the droppings. (6) Bury or burn diseased birds that have been destroyed. (7) Immediately isolate birds showing any signs of sickness. (8) After touching diseased birds disinfect the hands before handling other birds. (9) Thoroughly clean and disinfect lofts contaminated by disease. _b._ LOFT CONDITION. Pigeons must never be crowded in the loft. It is best to subdivide large lofts into smaller compartments for better control and ease of observation. Sunlight and dryness are two great natural disinfectants which should be utilized fully through plenty of window space and adequate ventilation. Eliminate strong direct drafts because they chill birds and lower their resistance to disease. 49. Control of Disease _a._ Pigeons showing any signs of sickness must be segregated immediately. In combat lofts there is normally no place available to isolate and treat diseased birds, therefore, it is usually advisable to destroy them and burn or bury their remains to avoid contaminating the rest of the flock. _b._ In any case of disease, the loft should be thoroughly cleaned and disinfected to destroy the germs of the disease as well as the mites and lice which may be carriers. Cresol, saponated solution, is an efficient disinfectant when used in a 4-percent solution in warm or hot water. This disinfectant is issued to signal pigeon companies. 50. Anatomy and Physiology A knowledge of the structure and function of the bird’s body helps a pigeoneer understand his birds and certain of their diseases. For convenience, the various organs are divided into groups or systems according to their functions. _a._ RESPIRATORY SYSTEM. (1) Mouth and nostrils admit air. (2) Glottis or larynx is the opening into the trachea. (3) Trachea conducts air to and from the lungs. (4) Lungs are organs of gaseous interchange. Air spaces are surrounded by a network of capillaries. Here the blood gives off carbon dioxide and takes on oxygen. (5) Nine air sacs cool the pigeon, give it buoyance, and mechanically aid the pigeon to breathe. _b._ DIGESTIVE SYSTEM. (1) Mouth is the opening through which food is received. (2) Esophagus conducts food to the crop. (3) Crop, or ingluvius, stores and softens the food.