VETEEINAEY MEDICIIvE. 885 



The conclusions are " that some immunity was produced by the use of 

 bovovaccine, but that this immunity did not remain to any appreciable extent 

 after the third year. We can not recommend the use of bovovaccine to stock 

 owners." 



Data were collected as to the use of tubercuUn in the diagnosis of tuberculosis 

 in cattle as shown in over 4,000 tests. The most valuable material was that 

 on the retesting of recently tuberculinized cows. Some experiments were un- 

 dertaken to verify Vallee's procedure for retesting cows 48 hours following a 

 previous injection of tuberculin (B. S. R., 16, p. 510"). It had been previously 

 observed that sometimes tuberculous cattle would not react to a double dose of 

 tuberculin on retest, even after a period of 3 months, this failure to react 

 being especially frequent in nonlactating cows, i. e., those that had been pur- 

 posely dried up and segregated because of the fact that they had reacted. 

 When opportunity was afforded to autopsy such cows, the lesions were some- 

 times foimd encapsulated, but in 6 instances active tuberculosis had been proved, 

 2 of which were also proved to have excretions virulent to guinea pigs. 



The test was made on 37 cows in full lactation. " In corroboration of Val- 

 lee's observations, in the retests made within 5 days the animals reacting to 

 the second injection usually had a rise of temperature sooner than at the first 

 test, but the only conclusion to be drawn is that the retesting of cattle within 

 6 weeks is not satisfactory, even when a double dose is used, and the tempera- 

 ture taken every 2 hours from the time of injection until the eighteenth hour." 



In another instance 20 reacting dairy cows were removed from a dairy, 

 dried up, and turned into a mountain pasture. When retested several months 

 later 18 of these 20 failed to react. It is not believed that the cows were 

 cured, but that rather the possibilities still exist that they may eliminate tu- 

 bercle bacilli and become a menace to younger susceptible animals. The 

 author therefore believes that no retests should be permitted. 



The history of tuberculosis in the college herd, H. H. Havnee {Pennsyl- 

 vania Sta. Bui. 12S, pp. 3-20, figs. 5). — This deals with the history of tubercu- 

 lous animals in the herd of the Pennsylvania Station. The first tests were 

 made in 1892, with no reactions. In 1906 there were 20 reactions in the herd ; 

 in 1907, 1 reactor; in 1908, 4; in 1909, none; in 1910, 5; in 1911, 12; and in 

 1912, 13 reactors. Following each of the tests the reactors were at once placed 

 in quarantine away from other animals or immediately slaughtered under 

 inspection. 



Records were kept of the 5 animals of the quarantine herd in 1910 as to the 

 general health and condition of each individual until disposal; their behavior 

 when subjected to the tuberculin test semiannually; their transmission of the 



in 



disease to healthy animals under open-air conditions ; and the post-mortem find- 

 ings. In most instances the animals of 1910 took on flesh and when slaughtered 

 were in very good condition. In the pre- and postinjection protocols no typical 

 reaction was noted at the outset, but semiannual retests in some cases gave more 

 specific reactions. Six healthy calves kept with the quarantine animals for 

 from 5 weeks to 3 months were found free from tuberculosis upon slaughter. 

 The post-mortem findings of all the animals are given. 



Tests made with beef breeding cattle kept in open sheds in winter and in the 

 pasture in summer during the last 2 years have failed to reveal any tubercu- 

 lous cattle. The beneficial effect of light, ventilation, and good feed as an aid 

 in preventing tuberculosis is considered, and the effect of constitutional dis- 

 orders and the presence of other tuberculous animals in the herd in favoring 

 the disease are pointed out. The application of the tuberculin test and the 

 disinfection of barns are discussed, with recommendations. 



