SOME l:XPHRnil-\T STATION WORK RI-LATIXG TO THE 

 PRODUCTION AND SALIi OF RIRI: MILK. 



By II. W. Lawson, Office of Experiment Stations. 



There is a rapidly decpenino; pulilic interest in all matters relating 

 to pure food, and this is especially true of milk yn account of the 

 extensive use of this product in the feeding of infants and invalids, 

 with whom the injurious eifects of unwholesome food are most 

 marked. AMiile the sanitary aspects of milk production have not 

 perhaps been the most prominent feature of the dairy investigations 

 at the agricultural experiment stations in the United States, matters 

 relating thereto have nevertheless recei-ved much careful attention. 

 Station dairymeif everywhere have urged the observance of the con- 

 ditions essential in the production and sale of pure milk, and to this 

 end have made free use of the op}K)rtunities afforded by the press, 

 farmers' institutes, dairy associations, agricultural college courses, 

 and station bulletins. In addition to this educational work, the 

 importance of which it is difficult to estimate, there has been con- 

 siderable experimental work relating to the purity of milk supplies, 

 some of which has been along comparatively new lines, but more of 

 which has been in the nature of demonstrations serving to establish 

 more firndy methods already known. 



The purity of milk may be affected by various factors, including 

 (1) diseases of cows ; (2) feeding stuffs; (8) condition of stables and 

 yards; (4) manner of milking; (5) methods of handling milk, such 

 as straining and aerating; (6) presence of bacteria, and (7) the use 

 of preservatives. To some of the more important results of experi- 

 mental work at the stations, relating to the production and sale of 

 pure milk, grouped for convenience under these headings, brief refer- 

 ence will be made in the following summary : 



DISEASES OF COWS. 



Of the diseases of cows which may be transmitted through milk, 

 tuberculosis is of most imi)ortance. Animals })laced under experi- 

 mental conditions have freciuenlly acquired the disease in this way. 

 While authorities are still at variance as to the unity of different 

 foi'uis of tuberculosis, it may be considered as conclusively estab- 

 lished that tubercle IjaciHi of human origin may i)rodu('e tyi)ical 



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