29 



chases should be isolated or kept apart from the healthy herd and, if possible, 

 from each other for at least three months, wlien they should be re-tested to 

 make sure they are healthy before putting them with other cattle. 



SANITATION. 



Dark, dirty, crowded stables are favourable to tuberculosis. Under tliese 

 conditions the disease spreads rapidly and is only kept out with difficulty. 



Clean, airy, well-lighted stables on the other hand, are unfavourable 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 necessary 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 thnt are constantly con- 

 fined 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; stablco 

 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 poisonous. An-imals 

 kept in such conditions become gradually reduced in vitality. This change 

 may not be noticeable to the observer, but becomes apparent if the animal is 

 exposed to disease. It readily contracts disease and does not recover from it 

 tfadily. 



Stables should therefore have plenty of air space for each animal. This 

 requires the ceiling to be high, the stalls roomy and the passages wide. In 

 addition to this ample air space, some way of changing the air in a stable must 

 be provided. This is done by suitable openings in the walls and roof and com- 

 prises the system of ventilation. 



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. E'o system is good that fails to accomplish these objects, 

 without causing unnecessary draughts. 



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

 weather, through ventilating shafts, which may be concealed 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. 



