60 DAIRY BACTERIOLOGY 



more serious consequences. To avoid the introduction of dirt 

 into the milk in filling or emptying the pails, cans or churns during 

 weighing or measuring, care must be taken that these vessels do 

 not become soiled during transport, and especially that they do 

 not become plastered with mud round the bottom rim where they 

 will be gripped on emptying. The cans should be covered with 

 tarpaulin during transport, and they should not be stood on the 

 ground but on clean planks. 



The possibility of infection being carried by Flies is by no means 

 to be overlooked as microorganisms may be brought from any 

 place where the flies may have lodged. In cowsheds the danger 

 is best avoided by removing the dung as often as possible and by 

 hanging up, just below the ceiling, wide shallow enamelled dishes 

 containing skim milk to which four tablespoonfuls of formalin 

 have been added per litre (or quart). 



To ensure fresh air during milking, the cowshed must be well 

 ventilated beforehand, and as many doors as possible be kept open 

 during the milking ; in this way, the additional advantage of a 

 good light will be secured. Cleaning operations of any kind or 

 feeding should be avoided just before or during the milking, in 

 order that the air may be as free from dust as possible. Naturally, 

 it would be an advantage if the hindquarters of the cows could be 

 brushed down just before milking l ; but the evil effects of the 

 dust raised in the process are only to be avoided if a special 

 milking room is available. Fig. 53 illustrates the room set aside 

 for this purpose at Fauerholm, near Frederiksborg. whence the city 

 of Copenhagen receives its highest grade milk, which is known as 

 " Ismaelk " (ice milk), as it is received into pails specially designed 

 by Busclc, which are provided with jacketed bottoms containing 

 a freezing mixture. 



The milk is (or should be) strained on the farm, in order to 

 remove the coarsest of the dirt particles. By means of Ulander's 

 filter, in which the filtering medium is a layer of cotton wool, 

 most of the finer dirt particles may also be removed. Although 

 the renewal of the cotton wool each time it becomes choked may 

 entail some expense, this filter is strongly to be recommended, as 

 the benefit to be derived from the immediate removal of the dirt 

 is incomparably greater than that derived from the subsequent 

 cleaning which the milk may receive on arrival at the dairy, when 

 the soluble dirt and the bacteria contained therein will have 

 become distributed throughout the milk owing to the shaking of 

 the cans during transport. The best practice of all is to prevent 

 the dirt from ever entering the milk by tying a straining cloth over 



1 In the procurement of the American " certified milk " the cows are 

 often vacuum cleaned before milking. 



