178 CLEAN MILK 



drainage; (3) the temperature at which milk and cream are kept; 

 (4) general cleanliness, requiring the absence of flies and dust. 



Inspection of farms is by , far the most valuable of all in- 

 spections relating to milk. Laboratory examinations in the city 

 will not take its place. Laboratory examinations will not dis- 

 cover any of the special germs most dangerous to man, as those 

 of tuberculosis, typhoid and scarlet fever and diphtheria, or those 

 derived from diseases of the cow — that is the usual routine exam- 

 ination. Hence regular veterinary inspection is indispensable. 

 Cows suffering from disease of the udder, as from the common 

 forms (colon bacillus, streptococcus, or staphylococcus, B. necroph- 

 orous infection) of mastitis, or tuberculosis, actinomycosis, or bo- 

 tryomycosis of the udder; or from septic metritis, parturient apop- 

 lexy, retained after birth, vaginal discharge, gastro-enteritis, diar- 

 rhea, constipation, suppurating lesions, foot rot, necrosis, tetanus, 

 fever, mange, or any severe constitutional disease, or cows recently 

 with calf or about to calve, should be debarred from supplying 

 market milk and the sick animal should be removed from the barn 

 in most cases. Not only this but if any contagious disease exists 

 among cows, as tuberculosis, foot and mouth disease, black quar- 

 ter, cow pox, milk sickness, anthrax, lung plague, septic en- 

 teritis or mastitis, or septicemia or rabies — the milk of the whole 

 herd should be refused and, after the disease is past or the cows re- 

 moved, the premises must be thoroughly disinfected (see p. 346). 



It is wiser that all inspectors of farms should be veterinarians 

 and they should have had previous training in the production and 

 handling of clean milk. Some authorities state that half the farm 

 inspectors should be veterinarians and the rest trained dairy in- 

 spectors. The frequency of examination of farms depends upon the 

 results of bacteriological examinations of milk. The farms supply- 

 ing the dirtiest milk need the more frequent inspections. In- 

 spections should be made once a month if possible. Certified milk 

 farms should be inspected weekly. The veterinary inspector must 

 rely partly on the information given him as well as upon his obser- 



