MALIGNANT CATAERH. 469 



also involved. It is first catarrhal in character, but soon a false or 

 diphtheritic membrane is formed, with the production of shallow 

 ulcers. There is dribbling of saliva from the mouth and discharge 

 from the nose, at first watery, becoming thicker and mixed with blrnd 

 and small masses of cast-off croupous membrane, causing a very fetid 

 odor. These croupous areas when they form in the throat, larynx, or 

 windpipe, may lead to narrowing of the passages, with consequent 

 difficult breathing and even suffocation. Various respiratory mur- 

 murs may also be heard, caused by the to-and-fro movement of mucus 

 and inflammatory deposits along the air passages. There is also 

 inflammation of the horn core with consequent loosening of the horn 

 shell, and the horns are thus readily knocked off b^' the uneasy, blind 

 sufferer. The animal may refuse all feed from the time of the initial 

 rise of temperature, or in less severe cases, and especially when the 

 lesions of the digestive tract are not so marked, the appetite may 

 remain until the disease is well advanced. Constipation is quite 

 common at the commencement of the attack, followed by diarrhea 

 and severe straining, the evacuations becoming very soft, fetid, and 

 streaked with blood. Cases of the evacuation of desquamated patches 

 of diphtheritic membrane from the intestinal mucosa 6 to 9 feet in 

 length have been reported. The kidneys and bladder are usually 

 inflamed, the urine being voided with difficulty and the animal 

 evincing signs of pain. Inflammatory elements, as albumen, casts, 

 etc., may be seen on examination of the urine. In cows the mucous 

 membrane of the vestibule is congested, swollen, and may contain 

 ulcers and an excessive quantity of mucus. Abortion during ad- 

 vanced pregnancy is not infrequent, following a severe attack. In 

 connection with these various symptoms there may be much uneasi- 

 ness on the part of the animal, leading in some cases to madness and 

 furious delirium, in others to spasms and convulsions or paralysis. 

 A vesicular eruption of the skin may occur, seen principally between 

 the toes and on the inside of the flank and in the armpits, with sub- 

 sequent loss of hair and epidermis. 



Like other infectious diseases, malignant catarrh pursues a longer 

 or shorter course in accordance with the severity of the attack. In 

 acute cases death is said to take place three to seven days after the 

 appearance of symptoms. Recovery, if it occurs, may take three or 

 four weeks. According to statistics, from 50 to 90 per cent of the 

 affected animals die. 



If animals which have died of this disease are examined, in addi- 

 tion to the changes of the mucous membrane of mouth and nasal cavi- 

 ties referred to above, shallow ulcers in these situations will be found 

 occasionally. These necrotic processes may pass l)eneath the mucous 

 membrane and even involve the underlying bony structure. In severe 



