CATTLE PLAGUE. 139 



On the day following the eruption in the mouth, or about 

 seventy-two hours after the first elevation of temperature, the 

 animal may be observed to be a little ill, to have less appetite 

 than usual, and to ruminate irregularly. Even at this time, 

 however, the pulse may be unaltered. On the following day, 

 the fourth from the first rise of temperature, the animal, for 

 the first time, shows marked symptoms of illness; and this 

 period, which may be one hundred and ten hours after the real 

 commencement, is usually considered by superficial observers as 

 the beginning of the disease. The seriousness of the oversight 

 is obvious, on account of the great importance of the earliest 

 possible separation, isolation, or more particularly the slaughter 

 of the diseased animal, and of all cattle with which it may have 

 been in contact. 



After the fourth day is over, the constitution is thoroughly 

 invaded. Then ensue the urgent symptoms — the drooping head, 

 hanging ears, distressed look, rigors and twitchings of the super- 

 ficial muscles, failing pulse, oppressed breathing, foetid breath, 

 and the discharge from the eyes, nose, and mouth. 



During the sixth day there occurs a great diminution of the 

 contractile force of the heart and voluntary muscles, the pulse 

 becomes feeble and thready, the respiratory movements are 

 modified, and the animal sometimes shows such weakness in the 

 limbs that it has been thought that some special affection of the 

 spinal nerves must exist. The temperature now rapidly falls, 

 and signs of a great diminution in the normal chemical changes 

 in the body present themselves. 



Death usually occurs on the seventh day from the first per- 

 ceptible elevation of temperature. 



Although this is given as the typical course of the disease, 

 there are great deviations from it, as some animals live a longer, 

 many a much shorter time, and the severity and sequence of the 

 symptoms vary considerably. 



The disease is induced by a microbe, which causes the for- 

 mation of a ptomaine, for, coincident with the first elevation of 

 temperature, and, of course, long before there is the least out- 

 ward appearance of ill-health, the blood of an animal which has 

 taken the disease contains an agent which can produce the 

 plague in another animal In other words, the earliest fact 

 which can be made out after infection is, that the blood contains 



