Cattle Plague. 679 



The heart is usually pale except in the spots infiltrated by 

 blood, but it may be mottled with petechise and particularly on 

 the endocardium. The pericardial fluid is often red. The blood 

 is at first little altered, but later undergoes marked changes, 

 notably an increase of fibrine (50 per cent.) and a decrease of 

 water (as in Asiatic cholera). There is marked leucocytosis, and 

 distortion of the red globules. Before death it becomes black and 

 incoagulable. 



The whole capillary system tends to be relaxed and over-dis- 

 tended (congested). 



Incubation. As seen in England the incubation was from four 

 to five days. Four to nine days are claimed by Galtier as the 

 extremes, yet he quotes incubations apparently as short as 12, 24, 

 36 and 48 hours respectively. A source of fallacy rests in the preva- 

 lence of cattle plague in the district and the possibility of infection 

 through unsuspected channels, before the recognized exposure. 

 Something must also be allowed for the greater susceptibility and 

 the larger dose of the poison which would tend to shorten the incub- 

 ation. Thus the western improved breeds, which suffer a mortality 

 of 80 to 95 per cent. (Refik Bey), and the winter season, when 

 the virus is concentrated in small ill ventilated houses, both tend 

 to shorten the incubation. At the Albert Veterinary College in 

 1865, Gerlach went direct from the infected stable to the sound 

 one, and in 48 hours several of the cattle in the latter had a mani- 

 fest rise of temperature. RolofI observed the elevation of temper- 

 ature in 36 hours after exposure, and Raupach and Ravitsch as 

 early as 1 1 hours after the inoculation. 



Symptoms. The earliest symptom is abrupt hyperthermia, 

 (104° to 108° P.). This is virtually pathognomonic in a herd or 

 locality in which the disease exists, or insuspected animals presum- 

 ably coming from an infected region. The temperature usually 

 rises to its height on the third or fourth day, and falls materi- 

 ally when other symptoms are developed. In some instances 

 death supervenes during the high temperature, but in the ma- 

 jority the temperature goes below the normal before death. 



Often on the second day, or the third, white epithelial eruptions 

 or concretions appear on the inner sides of the lips, closely resem- 

 bling the eruption of muguet (thrush) and often showing also on 

 the dental pad of the upper jaw and along the gums of the lower. 



