MILK HERDS 50? 



Freedom from Disease. 



The milk of no cow should be used unless the cow itself 

 is free from disease, particularly disease of the udder. A cow 

 that eats its food and gives a fair supply of milk is in the 

 dairy farmer's view a healthy cow, and local diseases, erup- 

 tions on the udder, even ulcers, are not always looked 

 upon as circumstances prohibiting the use of the milk. Yet 

 they should be, for it is now well known that many serious 

 diseases exhibit only transient or comparatively slight symptoms, 

 and yet are infectious. Hence, any disease however insignificant 

 or local, especially if affecting the udder, be it eruption, ulceration, 

 or otherwise, and attended or not with a rise of temperature, 

 should be considered to render the cow absolutely unfit to 

 produce milk for human consumption so long as the illness 

 exists. Foremost among these diseases is tuberculosis, but such 

 conditions as contagious abortion, acute mastitis, mammary abscess, 

 or any form of udder disease, persistent diarrhoea (scouring), 

 actinomycosis, or febrile diseases generally, should be included 

 as conditions prohibitive of milking for human food. Care 

 should also be taken to protect other animals on the farm from 

 contracting disease. The infection of healthy animals by 

 tuberculosis, for example, takes place readily from cohabitation, 

 the bacilli gaining entrance by the respiratory organs in most 

 cases, but by the digestive tract in many, especially in calves 

 when suckled by diseased mothers ; and in calves, pigs, and other 

 animals fed on milk, or on dairy bye-products containing living 

 bacilli ; and in pigs when allowed to eat tuberculous matter found 

 in carcases and slaughter-house refuse given them as food ; pro- 

 bably, too, in rare instances, from eating the flesh of tuberculous 

 animals. It is to the buildings themselves, we must look some- 

 times for the chief source of infection, and to neglect of 

 disinfection and sanitation must we attribute, in a great measure 

 the continuance of disease and re-infections. There are on record 

 repeated instances of herds cleared out and new purchases made 

 with every care in purchasing, being followed by new cases of 

 tuberculosis ; so that too much trouble cannot be taken to 

 eradicate disease, to make sure that the buildings are aseptic 

 and that sufficient air space is provided, as well as a rational 

 system of ventilation, whereby pure air is admitted and foul 

 air driven out, and that properly trapped drains carry off the 

 liquid excrements, and prevent the return of noxious vapours. 



