242 CONTAGIOUS LUNG FEVER OF CATTLE. 



be driven by their attendants to other yards or pastures at a distance, or to the other 

 stock-yards", \rhere buyers may see them. The attendants on the foreign stock-yards 

 may drive such animals into the common stock-yards, but must not, on any account, 

 enter tliemselves. 



5th. The cattle intended for export must be transferred to the oceau-going ships 

 direct, or carried to them on boats that have never been used for convej-iug other 

 cattle, or that have been subjected to the most thorough disinfection subsequent to 

 such use. 



6th. It should be shown that the ocean-going vessels, in which the export cattle are 

 ehipped, have not carried, and do not now carry, any hides or other unmanufactured 

 products of cattle ; or, if they have previously carried such articles, that thoy have 

 been thoroughly disinfected since. 



PLEUE.O-Prn3U3IONIA— THE LL"NG PLAGUE — CONTAGIOUS LUNG DISEASE 



OF CATTLE. 



Pleiiro-pneumonia is a malignant contagious fever to which, as far as 

 known, cattle only are liable, and in them is accompanied by inflamma- 

 tion and other diseased conditions of the lungs and their membranes, 

 together with great prostration of the entke system. 



It proceeds "from a poisoned condition of the blood. How, when, or 

 where this poison was first generated it is impossible to tell. Nor is it 

 less difficult to determine its specific nature. So far as reliable informa- 

 tion has yet reached, it is never generated spontaneously, but depends 

 entirely on the introduction of a ^drus or contagion into the system of a 

 healthy animal. A single animal so infected infects the herd; the herd, 

 subdivided and scattered, infects other herds until in time large areas 

 of country have been visited and devastated by the fearful scourge. 



Beginning, as we have reason to believe, in the far-off East, and at a 

 remote date, its course has been westward until, crossing the Atlantic 

 in the system of stock imported from European states, it has at length 

 found lodgment here. 



The earliest symptoms of the disease are not always easily detected, 

 there being no intensity of inflammation at first, and the period of in- 

 cubation varying often from eight or nine days to three or four months. 

 The knowledge of the existence of the disease in adjoining States or 

 farms, or even in remote sections from which cattle have been tutro- 

 duced, should serve to put every one on guard and lead to frequent 

 thermometric trials even with cattle apparently hi perfect health. 

 While such trials would not, perhaps, in every case determine infallibly 

 the existence or non-existence of the disease, yet in a very large ma- 

 jority of cases— possibly in nine out of ten, and particularly if other 

 symptoms were present — they would lead to a right conclusion. The 

 trial is made by inserting the thermometer in the rectiun. If a rise of 

 temperature to 103c-106^ Fahrenheit is observed we may be reasonably 

 Bure that the disease exists, at least iu an incipient state. 



Its fiu-ther development is indicated by fits of shivering, often so slight 

 and transient as to escape the notice of all save the practiced eye ; by a 

 dull, staring coat, with (frequently) a rigid skin; by a harsh, dry cough, 

 the more apparent when the animal is made to move briskly; by irreg- 

 ular chewing of the cud; constipated bowels; excrement dry; urine 

 diminished, but with high color; and, in the case of cows, by a tailing 

 oft" in the quantity of milk. 



At an early stage of pleuro-pneumonia there is a liarsh sound ov roar 

 produced l)y'^the passage of air through the wind-i)ipo r.nd its subdivis- 

 ions, wliich'may sometimes be heard at some distance IVom the sick ani- 

 mal. Occasionally the air rushing through the bronchial tube (made 

 rigid by a mass of hardened king) produces a very decided whistling 

 noise. A somewhat watery discharge from the nose, increased in the 



