248 DISEASES OF CATTLE, SHEEP, GOATS, ETC. 



other for at least three months, when they should be retested to make 

 sure they are healthy before putting them with other cattle. 



Sanitation. Dark, dirty, crowded stables are favorable to tuber- 

 culosis. Under these conditions the disease spreads rapidly and is 

 only kept out with difficulty. Clean, airy, well-lighted stables, on the 

 other hand, are unfavorable to the development of the disease. If 

 brought into such a stable it does not spread so rapidly and is not so 

 difficult to get rid of as in the first case. A well-built, sanitary stable 

 need not be made of expensive material or of elaborate design, but 

 should have plenty of light, air, and drainage. 



Light is very important. Direct sunlight is a great destroyer of 

 germ life. Tubercle bacilli soon die if exposed to sunlight. It is a 

 disinfectant, always ready to work without cost. Sunlight is also nec- 

 essary to the health of animals. Men deprived of it for any length of 

 time, as prisoners in jail, become pale and lose the appearance of 

 health. Cattle that are constantly confined in dark stables become 

 lowered in vitality and are ready to catch any disease with which they 

 come in contact. For these reasons the cow stables should have plenty 

 of windows, on two or more sides, if possible, so that the sunlight can 

 reach every part of the interior some part of the day. 



Pure air is also very important. In badly ventilated stables the 

 air is breathed over and over again until it becomes more or less pois- 

 onous. Animals kept in such conditions become gradually reduced in 

 vitality. This change may not be noticeable to the observer, but be- 

 comes apparent if the animal is exposed to disease. It easily contracts 

 disease and does not recover from it readily. 



Stables should therefore have plenty of airspace for each animal. 

 This requires the ceiling to be high, the stalls roomy, and the pas- 

 sages wide. In addition to this ample air space some way of changing 

 the air in a stable must be provided. This is done by means of suit- 

 able openings in the walls and roof and comprises the system of 

 ventilation. 



Ventilation to be successful must provide for two things first, 

 the removal of the foul air from the inside, and, second, the bringing 

 in of fresh air from outside the building. No system is good that fails 

 to accomplish these objects without causing unnecessary drafts. 



The usual way is to bring in fresh air through open windows, 

 and in cold weather through ventilating shafts, which may be con- 

 cealed in the walls or beneath the floor. The foul air is removed by 

 open windows and by ventilating shafts from the ceiling to the roof, 

 where they are usually protected by a hood. When both inlets and 

 outlets are proportioned to the size of the building there should be a 

 constant circulation of air and no sensation of closeness should be 

 perceptible in the stable. 



Drainage removes the liquid refuse from the stable by suitable 

 gutters and drains. It can not do this unless the floor is water-tight, 

 and concrete flooring is therefore recommended. Urine leaking 

 through cracks in the floor until the soil beneath is saturated is a fre- 

 quent source of foul odors and unhealthy stables. 



