242 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



with any organism. The sample of milk was in the majority of casea 

 divided into six lots, throe being pasteurized at a given temperature. 

 After the three samples of pasteurized milk cooled to 40° C. six were 

 inoculated with a given organism. One of the raw and one of the 

 pasteurized samples were placed in an incubator at o7° C, one of each 

 at room temperature (25° C.) and one of each in a refrigerator 

 (15° C). Bacterial counts were made of all the samples at various 

 intervals, to determine winch favored most the growth of the inocu- 

 lated organism. The organisms used for inoculation were Bacillus 

 prodigiosus, B. pyocyaneus, B. staphylococcus, B. aureus, and anthrax 

 vaccine. 



Comparisons were also made of heated and unheated milk serum 

 and of raw milk serum with horse serum. The keeping quahties of raw 

 milk and of milk pasteurized at various temperatures were compared. 



The pasteurization in all instances was done by immersing the 

 samples in water with a tiiermometer placed in the milk for recording 

 Lhe temperature. 



No definite conclusions could be drawn regarding the bactericidal 

 property of raw milk, as the results varied. The raw-milk serum 

 showed no superior bactericidal property over the pasteurized serum. 

 Pasteurization aided in the keepmg qualities of milk, depending upon 

 the length of time and the degree of temperature. 



THE BIOCHEMIC DIVISION, 



The work of the Biochemic Division, of which Dr. M. Dorset is 

 chief, has consisted of laboratory work mcident to the meat inspec- 

 tion, laboratory research work relating to meat products, investiga- 

 tions concerning hog cholera, the examination and preparation of 

 stock dips, and the preparation and distribution of tuberculin and 

 mallein. 



LABORATORY MEAT INSPECTION. 



The laboratory meat inspection is carried out by a central labora- 

 tory and six branch laboratories located in as many different cities. 

 At the beginning of the fiscal year a comprehensive plan for the 

 collection and examination of samples, based upon the preceding 

 year's experience, was adopted, and has been followed throughout 

 the year. The result has been to enable the laboratories to do con- 

 siderably more work, thus rendering the inspection more complete 

 and thorough without increasing the cost. 



During the fiscal year the laboratories examined 25,818 samples 

 of all kinds. These examinations included inspection for the pres- 

 ence of prohibited preservatives, prohibited coloring matter, adulter- 

 ants, and unwliolesomeness in meat and meat .food products of 

 various kinds, and the examination of salt, spices, condiments, 

 cereals, and other articles used in the preparation of meat food prod- 

 ucts. They include also the sanitary examination of a large number 

 of different water supplies. 



These samples were drawn chiefly from houses at which meat 

 inspection is maintained, and they show that in inspected houses the 

 use of prohibited preservatives and coloring matters is not practiced. 

 In a very small fraction of 1 per cent of all the samples examined 

 prohibited preservatives were found, but this was evidently due to 



