BACTERIA IN THE INDUSTRIES 187 



The animals should be tested for tuberculosis every six months. As soon 

 as an animal gives a positive reaction for tuberculosis, it should be removed 

 from the herd and killed. Milk from sick animals should not be used. 



b. The sanitary conditions and environment of pasture, grazing lands, 

 sheds, stables, etc., should be excellent. The entire water supply should 

 be pure, and all water supplies should be tested chemically and bacterio- 

 logically at suitable intervals. All food supply for cows must be whole- 

 some and free from objectionable contaminations. 



c. Those employed about the establishment must be free from latent or 

 active disease. They should be tested for tuberculosis, latent typhoid, 

 and should be examined for skin diseases. They must be cleanly in their 

 habits. Before milking, the hands of the milkers and the teats of the 

 animals should be washed with clean warm water and then dried with a 

 clean towel. 



d. The containers must be sterilized thoroughly every day, inside and 

 outside. This can be done by thoroughly washing and rinsing in boiling 

 hot water and thoroughly drying, before pouring milk into them. 



e. Just as soon as the milk is drawn, it should be bottled (sterilized 

 bottles), bottles capped, hermetically sealed (paraffin), and placed on ice 

 until ice-cold, and delivered at once to the consumer. The bottles should 

 be on ice in delivery, and, even though hermetically sealed, should be kept 

 away from dust and dirt. The bottles should be placed in paper 

 bags so that the driver need not touch them at all. The housewife 

 should take the bottle from the bag and place it in the ice-chest, 

 cellar, or cooler until the milk is wanted for use. 



Milk, on standing, should show no dirt deposit. This crude test is a 

 fairly reliable guide as to the sanitary conditions in the dairying establish- 

 ment and the rules of cleanliness that are observed. It has been shown 

 that the quantity of bacteria in freshly drawn milk is directly proportional 

 to the amount of dirt (sediment) present. A bottle or tumbler full of milk 

 should show no dirt sediment after standing for an hour or longer. 



Good cows' rnilk should have from 3.5 to 4.0 per cent, of butter fat. 

 It is marketed in three forms: Full milk having all of the butter fat, half 

 milk or partially skimmed milk, and skimmed milk. Because of the 

 variability of milk which is partially skimmed, it would be wise to with- 

 draw it from the market. When milk is sold without further specification, 

 full or unskimmed milk is understood. It is unlawful to sell skimmed 

 milk as milk, or without designating it as skimmed milk. 



In some countries, as Germany for example, the rules and regulations 

 directed against dairies, dairying and the sale of milk, are very f ar-reaching, 

 and are strictly enforced by the local health authorities. Specific rules are 

 laid down as to what milk may or may not be marketed, how the cows are 



