144 BOVINE PATHOLOGY. 



circumstances the prognosis must be favorable, as re- 

 covery will take place after from eight to twelve or 

 fifteen days from the premonitory rise of temperature. 

 The various complications which we have just noticed 

 necessarily protract the case, but our prognosis, too, must 

 include grave loss to the owner, especially when milch 

 cows are affected. From the first stage of the attack the 

 milk is yellow in colour and gradually diminishes in 

 quantity until it becomes about one fifth the natural yield. 

 Its specific gravity is low, 1024, and it generally has a fair 

 proportion of cream. White corpuscles, having the 

 characters of pus-globules, are always present, their 

 number varying with the severity of the symptoms. 

 Some of these were seen three weeks after recovery. 

 Monads and bacteria were observed in every specimen, 

 and remained unaffected by boiling (Professor Brown). 

 The produce of a dairy, then, is venj seriously diminished 

 by an attack of eczema. In the severer forms, too, 

 abortion occurs, and in all cases the animals are very much 

 reduced in condition ; 10 per cent, is given as the average 

 loss by death when the disease is most severe. One attack 

 of this disorder does not secure immunity from others ; it 

 is not rare to see animals which have been affected three 

 times. From cattle, who are especially affected by it, and 

 are the most important bearers of contagion, it will 

 spread to the sheep, pig, poultry, and also to the human 

 subject and the horse. The cases which have been 

 recorded can leave no doubt of this latter fact. The con- 

 tagion is both fixed and volatile, so that the disease is 

 contagious and infectious. The characters of the materies 

 morbi have not yet been determined. Professor Brown 

 mentions the occurrence in the blood and other fluids of 

 monads, bacteria, and vibriones^ but does not attribute a 

 specific influence to any of the observed forms. The 

 viruliferous principle resides in its most concentrated 

 form in the saliva. In 1839, Professor Simonds com- 

 municated the disease by feeding an animal on hay 

 saturated with saliva ; vesicles appeared in the mouth in 

 forty hours. He also found that warm milk from a 



