488 ANNUAL REPORT OF THE Off. Doc. 



A disease so varied in its attacks must have a very great variety 

 of symptoms; but you can safely say to the farmer that any symp- 

 toms of decline in flesh, shrinkage of milk, cough or any other symp- 

 toms out of the ordinary, while the animal continues to eat well may 

 be regarded as suspicious and the animal exhibiting such symptoms 

 should be taken away from the rest of the herd until a correct diag- 

 nosis can be made. If this plan could be carried out, a great many of 

 our valuable animals could be saved, for if animals affected with 

 tuberculosis are permitted to remain with other animals it is cer- 

 tain to spread and it is in this way that infection becomes so ex- 

 tensive in some of our herds. 



The farmer should be cautious in buying recruits for his herd. It 

 is estimated that eight out of every ten cases of infected herds from 

 cattle that were supposed to be healthy when purchased and be- 

 fore any physical symptoms could be seen the herd had become ex- 

 tensively infected. 



Among the chief influences governing the spread of tuberculosis 

 in a herd are stable management and stable construction. Hence 

 we can all see the necessity of keeping our stables well lighted and 

 ventilated. It is a fact that a majority of our stables are not as well 

 lighted as they should be. The value of light is determined by sev- 

 eral specific facts, viz: First, it has a decided germicidal action; 

 second, it increases the resistance of animals from attacks of tubercle 

 bacilli, and third, it favors cleanliness. 



It is a common sense matter of observation that dark, gloomy 

 stables are invariably dirty while light and well ventilated stables 

 are most always clean. It is a very poor farmer who will permit 

 dirt where it can be seen, and in my experience, a farmer who has 

 stables that are well lighted also enforces cleanliness. The two 

 go hand in hand. 



An ample supply of fresh air is desirable for three reasons: It 

 has a depressing influence on germ life, it increases the resisting 

 pow T ers of the animal and dilutes atmospheric impurities, at the 

 same time removing them. Where ventilation is bad, whatever im- 

 purities enter the air in a stable they are in a comparatively con- 

 centrated state and are therefore manifestly more dangerous than 

 when segregated and dissolved by an abundant supply of fresh air 

 that is in circulation by reason of a good system of ventilation. 



The hygienic value of cleanliness in a stable cannot be overesti- 

 mated for the reason that practical sanitary science is largely made 

 up of cleanliness. Exercise is also essential to perfect health. It 

 is a proven fact that the proper moderate use of any organ of the 

 body maintains it in health and that disuse leads to atrophy. I am 

 aware that some of our official publications and a few of our insti- 

 tute workers advise us not to exercise our cows. Common sense 

 and the laws of Nature do not sustain the theory. Take for example 

 the fish in the Mammoth Cave, Kentucky. They are blind. Or- 

 ignally these fish were possessed with normal eves, as there re- 

 mains a cicatrice of sufficient proportions to show their primal con- 

 dition. For thousands of years they have had no opportunity of 

 using their organs of vision and Nature has gradually eliminated 

 that important function. This is also true of deep sea fish and deep 

 sea life. 



A great deal has been said about the tuberculin test and I regret 



