110 \.\M AL KKPORT OF THE Off. i>oc. 



eases, a negative diagnosis in 18 cases, while the result was doubtful 

 in 9 cases. A large number of diseased or dead fowls were received 

 during the year. These included pigeons, squabs, chickens and 

 ducks. Examinations were made in each case and the consignor 

 was notified as to the result of the examination and was furnished 

 such advice as was appropriate. 



The demand for the biologic products of the laboratory has in- 

 creased a great deal. During the year the laboratory made and dis- 

 tributed 20,230 c. c. tuberculin, about GOO doses of nyillein and 836 

 doses of anthrax vaccine. The laboratory force has prepared the 

 vaccine for use in all of the experimental work and also for vac- 

 cinating cattle in several herds. This work of the laboratory is 

 destined to increase very greatly during the coming year. The labor- 

 atory has continued under the efficient direction of Dr. S. H. Gilli- 

 land. 



A rather interesting and instructive investigation was made during 

 the summer with relation to the milk produced by a herd in Wyom- 

 ing county. The owner of this herd brought to my notice the fact 

 that his customers complained that the milk, after it had been kept 

 a day or two, developed little pinkish points or spots upon the sur- 

 face. These pinkish areas gradually increased in size, and in depth 

 of color, until the surface of the milk presented red patches and, 

 from these, coloring matter went into the milk, giving the whole 

 body of the milk a pinkish hue. The customers who had first noticed 

 this unusual condition thought that the milk was contaminated 

 or that it had been treated with chemicals. These views were at 

 variance with my own knowledge of the intelligence and the high 

 character of the dairyman, who was very much worried by the condi- 

 tion which was of the greatest importance to him, as it threatened 

 to cost him his custom. It was evident, at once, that the difficulty 

 was caused by the growth of a pigment producing organism in 

 the milk. The fact that the trouble did not occur until the milk had 

 stood for a time pointed unmistakably to this conclusion. If the 

 red coloring matter had been due to blood or to a pigment intro- 

 duced directly as the milk was secreted or drawn, the red color 

 would have been most evident in the freshest milk. Since it is usual 

 in such cases for contamination to enter the milk after it is drawn 

 from the cow, instructions were given as to the disinfection of the 

 premises, the cleansing of the cows, the sterilization of the utensils, 

 and the disinfection of the place where the milk was stored, etc. 

 All of these recommendations were followed very faithfully, but 

 the trouble continued. Therefore, an examination was made of the 

 milk of each cow in the herd. Dr. E. S. Deubler went from the labor- 

 atory to the farm to make this examination. By drawing a sample 

 of milk from each cow into a sterile bottle and by setting these sam 

 plese aside for observation, it was found that the red color appeared 

 in the milk of but one cow. A further examination of the milk of 

 this cow showed that only the milk from one quarter of the udder- 

 became discolored upon standing. The pigment in this case was 

 produced by an organism resembling the Bacillus prodigiosns. The 

 cow was obtained for study and a series of investigations were made 

 with her milk. The organism causing the trouble disappeared com- 

 pletely after six weeks. It was possible to infect an uninfected 

 quarter of a cow's udder by injecting into the milk cystern a small 



