CONTAGIOUS LUNG FEVER OF CATTLE. 243 



act of conghing, is noticed early iu the disease, and dri\-ing sick cattle 

 in the earliest stage produces much thirst, and there is sometimes a ropy 

 saliva discharged from the mouth, while the muzzle is hot and diy. 



As the malp^dy progresses the pulse rises to seventy, eighty, and even 

 a hundi-ed beats per mmute ; the respirations to thirty-five and forty 

 per minute, and are labored and audible, while each expiration is ac- 

 companied in most cases by a short distnictive grunt or groan, the more 

 marked whenever iiressure is apphed to the ribs over the lungs. 



At this stage the cough increases, the gait becomes more languid, the 

 eyes more prominent and fixed ; the countenance assumes an uneasy, 

 pained expression, and a disposition is manifested by the sick to sepa- 

 rate from the well. When the animal stands the elbows are turned out, 

 the fore limbs extended, the hind feet dra^Mi forward under the body, 

 the head and neck stretched out, and the back arched, while the nostrils 

 are more or less convulsively expanded at each inspiration. When lying, 

 to which there is a tendency, the animal rests, especially in the latter 

 stages of the disease, on its brisket, or on the affected side, leaving the 

 ribs on the healthy side as much freedom of motion as possible. 



With a still further advance in the disease, the pulse becomes more 

 frequent (often rising to 120 per minute) and the heart-beats, at first 

 subdued, are now marked and palpitating ; the tongue becomes foul and 

 covered with fur, and the breath has a nauseous smell. Listlessness, 

 grunting, grinding of the teeth, diminished secretions, and weakness 

 rapidly increase ; the breathing is more frequent and labored ; the animal 

 gasps for breath; the spasmodic action of the nostrils is more marked, 

 the groan more audible ; the temj)erature is irregular, the tendency being 

 to coldness of the horns and extremities. These conditions are followed 

 by a mattery 'or watery discharge from the eyes and nose, rapid loss of 

 flesh, hide bound, and either obstinate constipation or else a violent 

 watery diarrhcea of foetid matter associated often with a considerable 

 discharge of clear-colored urine. 



Percussion over the lungs wiU, in the beginning, often reveal the dis- 

 ease when not otherwise api)arent. W^ith some practice and a little care 

 almost any one can distingTush the sick from healthy cattle by listening 

 to the sides of the chest. In the earher stages of the disease percussion 

 gives out a clear or resonant sound, followed, as the malady increases, 

 by a dull, heavy one, easily distinguished from the sound caused by 

 the lungs in health. 



Where one lung only is affected, partial, sometimes complete, restora- 

 tion may result ; but acute pleuro-pneumonia, in which both lungs are 

 affected, we may safely assert is never terminated except by death. 



As stated above, the period of incubation of this disease varies from 

 eight or nine days to three or four mouths ; the usual average period 

 being from twenty-five to forty days. The acute stage of the disorder 

 varies from seven to twenty-one days. Convalescence extends over a 

 period of from one to three mouths, during the greater part of which 

 time the convalescent animal is often capable of infecting healthy cattle. 



As a rule, in mild outbreaks, the mortality attains twenty-five per 

 cent., and in severe epidemics sixty, seventy, or even one hundred per 

 cent. 



In England, the lung disease has more than doubled the ordinary 

 mortality of the country, entailing a loss of many millions of dollars. 



While various remedies for this insidious disease have from time to 

 time been recommended and tried, not one of them, nor all of them com- 

 bined, have proved a specific against its destructive efiects; aiul as a 

 means to be relied on for the protection of the stock of the country ^ they 



