350 ENZOOTIC AND EPIZOOTIC DISEASES. 



period of latency, between the reception of the poison and the first 

 manifestation of symptoms, is short but uncertain. To the febrile 

 symptoms succeed those of the specific effect of the poison upon 

 the mucous membrane of the nose, eyes, throat, and respiratory 

 track, as well as the intestinal mucous membrane and its ramifi- 

 cations in the biliary tubes. In some cases, the genito-urinal 

 mucous membrane may participate in the inflammation, and in 

 the majority there is more or less sympathetic or actual irritation 

 of all the mucous membranes of the animal body. 



In the majority of instances the fever precedes the catarrhal 

 symptoms ; the rigors, increased frequency of pulse, and eleva- 

 tion of temperature to 103° or 104° Fahrenheit, being observable 

 prior to the appearance of any localization of the disorder. In 

 other instances the irritation of the mucous membrane has been 

 the first appreciable sign. 



In uncomplicated cases the fever begins to abate in from three 

 to five days, leaving the animal weak and prostrate. 



It cannot be said that the fever terminates in a critical dis- 

 charge, as in the human being. All that can be observed is 

 that, coincident with the abatement of the fever, the secretions of 

 the body become natural or slightly increased ; the critical sweat, 

 diuresis, or diarrhoea so generally observed in the human being, 

 are usually absent in the horse. 



Complications. — The catarrhal form is the one to be regarded 

 as the simple or uncomplicated ; to this is added, in some in- 

 stances, pulmonic, gastro-enteric, hepatic, and rheumatic com- 

 plications, peri- or endo-carditis, the formation of thrombi, and 

 nervous symptoms, as convulsive fits and coma. 



Symptoms of the catarrhal form. — Actual rigor may or may 

 not precede the other symptoms ; very possibly the rigor is not 

 observed. There is a dry, staring coat, the legs, ears, and nose 

 are cold, with redness and dryness of the Schneiderian membrane, 

 and an elevation of temperature to 103-4-5-7° F. or higher. There 

 is sneezing, a hacking cough, and shortly a defluxion, from one 

 or both nostrils, of at first a thin, more or less acrid mucus. 

 The eyes are lieavy, conjunctivae injected and sometimes yellow, 

 and tears flow over the face. The symptoms increase in inten- 

 sity for two or even three days. The discharge from the nose 

 becomes flaky and more profuse. In some cases the conjunctiva 

 of one or both eyes is actually inflamed, as marked by opacity 



