Milk Sickness. '' The Trembles:' 373 



In addition to ingestion as a cause, certain accessory causes 

 ought to be noted. Some men eat the infecting material with 

 impunity, while others succumb to the deadly disease. As the 

 observations have all been made in or near the infecting locali- 

 ties, individuals may be immune through a previous attack and 

 recovery, or there may be a native immunity through unknown 

 conditions. Young children often suffer less than adults, pos- 

 sibly because of the greater activity of their emunctories and 

 consequent elimination of the toxic products and the comparative 

 absence of exhausting or depressing conditions. Their purely 

 animal food (milk) may exercise an influence, and this may as- 

 sist in explaining the fact that certain adults appear to be 

 refractory. 



Fatigue, debility and ill-health are said to predispose the sys- 

 tem. Milk sickness attacks most violently those that have been 

 subjected to overwork or severe exertion of any kind, especially 

 in hot weather, those suffering from want of sleep (sitting up with 

 the sick), those having a special cause of mental depression, 

 those suffering from some illness — constipation, indigestion, ma- 

 laria, etc. 



Milch cows are probably more open to the attacks of the germ 

 because their systems are reduced by simultaneous milking and 

 breeding through a number of years. Exertion or fatigue has a 

 potent influence in developing the symptoms, so that it is a 

 common practice in the vicinity of infected localities to subject 

 animals to a good run before purchasing. Paradoxically enough 

 the infected milch cow which is distributing the infecting element 

 freely in her dairy products usually shows, in herself, no distinct 

 symptoms of the disease. If she is dry or farrow she suffers like 

 any other animal, but if in full milk, the toxins, and even the 

 Tiypothetical microbe, seem to escape in that secretion, which 

 proves highly poisonous to other animals, while the cow retains 

 her spirits, vigor and outward appearance of health. Steers, 

 IjuUs, and heifers, on the other hand, show violent symptoms. 



Calves suffer so long as they suck the milk. The dead calf is 

 eaten by swine, which suffer in their turn, and the dog contracts 

 the disease by eating one of these animals, or by taking infected 

 milk or cheese. The buzzard eats the dead dog and dies as the 

 result. 



