180 CELLS, DIRT AND DEBRIS 



workers have endeavoured to find a relation between the cell 

 count and the number of streptococci and other bacteria but 

 with no marked success. Milk stasis has been shown by many 

 observers to have a profound effect on the cell count by mark- 

 edly increasing the number of leucocytes. 



Whilst it is impossible to formulate any rigid standard for 

 individual cows the author believes that mixed milk con- 

 taining over 1,000,000 cells per cubic centimetre as determined 

 by the Savage or Breed methods should be regarded with sus- 

 picion and the supply at once investigated. An excessive cell 

 count is not sufficient, per se, to warrant condemnation of a 

 supply, but if other unsatisfactory conditions also exist, such as 

 large numbers of streptococci, the public should be protected 

 by the exclusion of the supply until the condition is abated. 



The tentative working basis of 1,000,000 cells per cubic 

 centimetre is not so low as to prevent the possibility of passing 

 a sample of mixed milk from a herd containing one case of 

 garget but is sufficiently so to provide a reasonable safeguard 

 without being oppressive on the producer. As a routine method 

 of milk examination, the cell count has little to commend it in 

 the case of herd milk, but in the examination of individual 

 cows it is often of great service. 



Dirt and Debris. During the present century many 

 attempts have been made to quantitatively determine the 

 amount of dirt and debris in milk. Several methods have been 

 used, but as there is no agreement as to what is to be regarded 

 as dirt these have given results which, although comparable 

 among themselves, bear no relation to each other. 



The sediment from milk according to Delepine ^^ consists of 



(a) Cells derived from the udders. 



(b) Hairs and cells from the milker, or cows or other farm animals. 



(c) Wool, cotton or other fibres from strainers, etc. 



(d) Vegetable and mineral matter derived either from food, dung or 

 litter or from dirty utensils and wash water. 



(e) Algae, moulds, and bacteria from various sources. 



As the cells and bacteria are separately determined, the 



