No. 6. DEPARTMENT OF AGRICULTURE. 145 



The primary and essential duties of the State Livestock Sanitary 

 Board, as ex})ressod hx law are, lu'otection of liealth of domestic ani- 

 mals and conservation of the livestock industry. It is through tlie 

 medium of these primary and essential duties that public health is 

 secondarily protected. It is this point that we desire to be thor- 

 oughly unders'tood by all livestock owners; also that we wish to ren- 

 der them every assistance within our jurisdiction and resources. 



We cannot render free veterinary service in all cases of animal 

 ailments for the reason that it would be too expensive for the State 

 and it would be an injustice to veterinarj'^ practioners who have pre- 

 pared themselves for the profession and pay an annual license to the 

 State. But we are always glad to co-operate with the attending 

 veterinarian by personal service or the use of our laboratory. Our 

 duties are largely limited to handling dangerous transmissible dis- 

 eases which are enzootic and occasionally become epizootic. 



Tuberculosis has never reached the proportions of an epizootic 

 and probably never will, owing to its slowly progressive nature. But 

 it is found to varying extent throughout the entire State. In the 

 thickly populated dairy districts the percentage of affected animals 

 is relatively large, while in other sections it is of irregular occur- 

 rence. In the dairy districts, where the economic importance of the 

 disease is more fully realized, much attention has been given to its 

 control by the use of the tuberculin test. 



This has made its extent in such districts more apparent than 

 real, as compared with other sections where the test is rarely em- 

 ployed. Although tuberculosis was not identified as a specific in- 

 fection until 1865, it is not a new disease. Professor V. A. Moore 

 in his work on the Pathology of Infectious Diseases of Animals 

 states: "Tuberculosis is one of the oldest diseases affecting cattle 

 of which there are any identifying records. It seems to have been 

 known to the Jewish people during their Egyptian captivity and 

 the ecclesiastical laws for many centuries contained numerous en- 

 actments against the consumption of flesh of tuberculous animals." 



It is a transmissible disease common to man and animals, and has 

 also been found in birds, fishes and reptiles; only in rare instances 

 has it been found in horses and mules. Sheep are susceptible and 

 will contract the disease if directly exposed to virulent infection, 

 but under ordinary conditions enjoy a high degree of immunity. 



Its greatest economic importance in relation to agriculture is the 

 extent to which it is found in cattle and swine. 



The disease does not arise spontaneously; every case has been 

 caused by infection from a previous case. The causative factor is a 

 microscopical germ which has been named the "bacillus tuberculo- 

 sis." This germ gains entrance to the body and lodges somewhere 

 in the tissues where it propagates and destroys healthy tissue by the 

 irritant poisons which it execrates. The principal ways in which 

 the germs gain entrance to the body are : Through the air, by breath- 

 ing and by contaminated food or water taken into the digestive tract. 

 Another mode of infection which is of less importance is through the 

 medium of diseased sexual organs, either by copulation or during 

 gestation. Only in comparatively rare instances does a tuberculous 

 dam infect the offspring before birth. Such a mother may have 



10—6—1915 



