DISEASES COMMUNICABLE IN MILK 53 



of years. (3) Perseverance is demanded of the owner, for final success can 

 be won by only persistent effort in the face of discouraging setbacks. 



In Denmark where the Bang system was developed there have been 

 formed by the farmers associations which enable the members to bring 

 their tubercular stock into a single herd and therefrom raise up sound 

 animals at a minimum of trouble and expense. The formation of similar 

 societies has been proposed in the United States but actually, none seem 

 to have been created. In some States there has been some discussion of 

 the suggestion that the State assist the farmers in the formation and care 

 of such herds, with the object of encouraging dairymen to establish herds 

 of tuberculosis-free animals and of conserving breeding animals of valu- 

 able dairy strains that are now butchered after reacting to tuberculin. 

 The proposition has some merit and no doubt in competent hands would 

 prove satisfactory but if conducted as a political sinecure it would do a 

 deal of harm. 



The Birmingham Method of Control. Savage has described a mode of 

 maintaining the Bang system in Birmingham, England, that might be 

 used in small cities in the United States. The city supplies farmers the 

 tuberculin and veterinary assistance necessary for testing their cows twice 

 a year. The farmer disinfects the stables and separates the diseased and 

 healthy animals. Tuberculosis-free cows are marked and those having 

 tuberculous udders are sold for slaughter. The city gives quarterly 

 certificates to owners of tuberculosis-free herds and keeps a public list of 

 their farms. In this way several sound herds have been built up and 

 more are on the way. 



Use of the Bang Method in the United States. -In the United States 

 and Canada private owners have built up tuberculosis-free herds and 

 so have several of the experiment stations, by the Bang method. The 

 Wisconsin Stations, the first to use it, began in 1896 with 16 reactors 

 and 18 well cows. In February, 1899, the herd had 27 well animals 

 bred from reactors. The New York Station in 1901 had 13 healthy 

 animals and 17 tuberculous. It lost four healthy animals by fire and only 

 a few heifer calves were born but in 1905 it had a herd of 30 sound and 

 six tubercular animals. The latter were slaughtered. The experience 

 in building up the herd at the Illinois Station has been told by Hayden. 

 In Table 26 appears a statement of the females in the herd, the number 

 tested and the number of reactors. 



There were several reasons for not testing the entire herd at different 

 times but usually the principal one was that many of the animals were 

 regarded as too young to test. 



Despite great loss, and with the addition of a few calves from another 

 herd, the number of females increased from 55 in 1907 to 91 clean females 

 in 1912. In the period 19 females were purchased and 32 non-reactors 

 sold. The herd was well-seeded with tuberculosis previous to 1908 and 



