No. 7. DEPARTMENT UF AGHICLLTLIIE. .157 



proximately 25 c. c. of plain bouillon. After an incubation of 24 

 hours with the development of a heavy growth, the culture is heated 

 to 00° for one hour, whereupon sub-cultures are made and the heated 

 culture is placed in three test tubes. The test tubes containing the 

 heated culture or vaccine are held for 24 hours and if at the end 

 of that time the sub-cultures made from the heated culture have 

 remained sterile, the three test tubes of vaccine are sent to the sender 

 of the specimen with directions that an injection may be made with 

 the vaccine from one of the test tubes, using as a dose, from 2 to 3 c. 

 c. The injection of vaccine may be repeated in from 5 to S days. 



The reports received of tlie results obtained from the use of the 

 vaccine prepared during the year, have been exceedingly encour- 

 aging in many instances and in others apparently no imi)rovement 

 was noted following the injections. 



SPECIMENS RECEIVED FOR EXAMINATKJN. During the 

 .vear, 1,012 specimens were received at the Laboratory, including: 



Rabies. 527 heads of animals were examined. Of these, 62 heads 

 of rabbits are included of which 30 were positive and 32 negative. 

 The rabbits served as experimental animals in those cases in which 

 the miscroscopic examination failed to sIkmv conclusive evidence. 

 Of the remaining 465 heads, 408 were dogs, 335 positive, 49 negative, 

 and 24 were not examined; 33 of cattle, 24 positive, 8 negative and 



1 not examined; 6 cats, 2 positive, 3 negative and 1 not 

 examined; 5 horses, 5 positive; 6 hogs, 4 positive, 1 negative and 1 

 not examined ; the brains of 3 human beings, all three positive (hy- 

 drophobia i ; 1 mule not examined; 1 sheep, positive; 1 deer, nega- 

 tive; one goat, negative. 



Tuherciilosis. 63 specimens were received for examination, in- 

 cluding. 45 from cattle, 5 from hogs, 4 from human beings, 4 chickens, 



2 cats, 1 dog, 1 horse and 1 parrot. The presence of tubercle bacilli 

 was demonstrated in 48, and in 15 the examination failed to reveal 

 the presence of the organism. The number of specimens examined 

 for tubercle bacilli is proportionately larger upon including the ex- 

 amination of the feces of 40 cattle, which w'as started in April and 

 completed in Septeinber. The general plan followed in the examina- 

 tion is as follows: 



Cattle. Forty in all were selected from those of the Experimental 

 Farm of the Pennsylvania State Livestock Sanitary Board. All of 

 the cattle upon the Experimental Farm serve wholly or in part in 

 experiments with tuberculosis. In the selection, cattle with tuber- 

 culosis and some free of tuberculosis were included under three 

 classes: 



1. Tuberculin reacting cattle with physical symptoms of tubercu- 

 losis. 



2. Tuberculin reacting cattle showing no physical symptoms of tu- 

 berculosis. 



3. Immunized cattle free of tuberculosis. 



Ufateiial for Exauihutthtii. Each uiorning for eleven days, a])- 

 proximately 75 grams of feces were collected in a sterile bottle with 

 a sterile glass slide from manure freshly dro]>ped by each animal 

 included in the examination. In the afternoon of each day the feces 

 was collected, a .smear preparation on a glass slide, of the feces 

 in each bottle was made for miscroscopic examination. The 75 



