188 EXPERIMENT STATION RECORD. 



Protective inoculation against foot-and-moutli disease of sheep, as prac- 

 ticed in the immunization of sheep and pigs, Loeffler and rnLExnuTn {Ber- 

 lin. Thicrarztl. Wchiixrhr.. 191)0, X». .52, j)},. 613-610).— A? previously reported, the 

 author? ha\'e i)roduced a perum which rendered young [Ag^ quite immune to this 

 disease. In doses of 0.1 cc. per kg., an immunity was produced which lasted for 3 

 weeks. In doses of 0.2 to 0.5 cc. per kg., immunity persisted for 8 weeks. The 

 same serum was used successfully in rendering cattle immune from foot-and-moutli 

 disease. Inununity in cattle, however, was only of short duration. In an outbreak 

 of the disease in a herd of 416 sheep, 28 sheep received an injection of serum 2 days 

 after the tirst appearance of the disease. The sheep were apparently well at the 

 time, l)nt 4 were sick on the day after vaccination. These 4 were probably infected 

 at the time they were vaccinated. All the other vaccinated animals remained 

 healthy. Foot-and-mouth disease broke out in a large herd of swine. A number of 

 the pigs were vaccinated, and all the vaccinated animals showed a perfect immunity 

 to the di.sease. The authors describe in detail the methods foi- obtaining the immun- 

 izing seruni in a rapid and convenient manner. 



The nature, cause, and economic importance of ovine caseous lymph- 

 adenitis, V. A. XoRGAARD ( r. S. Depi. Ac/r., Bureau uf Animal Industry Rpt. ISfiQ, 

 pp. 638-662, p)U. 7). — The first cases of this disease in the United States were reported 

 by Dr. 0. B. Hess, from Los Angeles, Cal. Later it was rejiorted from Chicago, 

 Omaha, and Kansas City by inspectors stationed at those places. Usually no charac- 

 teristic symptoms are observed in affected animals during life. The disease is 

 chronic and the pathological changes develop so slowly as to cause no striking inter- 

 ference with the health of the affected sheep. This is esj^ecially true of lambs and 

 sheep which are raised for mutton and which are marketed liefore they are 2 years 

 old. A careful examination of an affected sheep will disclose an enlargement of one 

 01' more of the superficial glands, the precrural and prescapular glands being most 

 frequently attacked. By metastasis the disease may attack the principal organs of 

 the body, causing a chronic broncho-imeumonia, with symptoms of coughing. 

 Several thousand cases are observed annually in slaughterhouses of the United States, 

 and the progress of the jmthological changes usually correspond to the age of the 

 animal. 



When first infected l)y the micro-organism of the disease the gland tissue enlarges 

 to several times its original size. Later an abscess is formed witli caseous contents of 

 greenish yellow color. In the liver i)athological changes are most fre(]nent!y in the 

 form of large nodules. The kidneys are seldom affected. 



The micro-organism of this disease is a short bacillus, with rounded v\n\<. It is 

 aeroliic and develops well upon glycerine agar or in peptonized beef bouillon, hut 

 most readily on blood serum. Bouillon containing 1 per cent of dextrose in fer- 

 mentation tubes indicates a fermentation in the ])urD with an acid reaction. The 

 organism develops most rapidly at a temperature of 37° C, and is destroyed by 

 exposure for 10 minutes to a temperature of 65° C, or 6 minutes of 70° C. An 

 exposure of 5 days to direct sunlight does not destroy the vitality of the organism. 

 Culture tubes kept at a temperature of 6 to 8°C. for a period of several weeks showed 

 an active development when subsequently incubated at a temperature of 37° C. 



In guinea pigs intravenous inoculations of from ,3 drops to 0.3 cc. caused death in 

 from 4 to 10 days. Intra-abdominal inoculations of from 0.3 to 0.75 cc. proved fatal 

 in from 8 to 15 days; while subcutaneous injections of from 0.25 to 0.75 cc. caused 

 death in from 15 to 28 days. Guinea pigs fed with oats infected with bouillon cul- 

 tures of the organism died after from 5 to 8 weeks. In rabbits intra-abdominal inoc- 

 ulation in doses of from 0.25 to 0.75 cc. caused death in from 20 to 32 days; while 

 ral)bits inoculated by the subcutaneous method did not die until from the 25th to the 

 38th day. Experiments on pigeons and fowls indicated that these animals are 

 imnume to the disease. Inoculation experiments with sheep produced a chronic 



