BLACK LEG-ITS SYMPTOMS AND TREATMENT. 



This disease occurs most frequently in young animals, those from 

 six months to two years old being most subject to it, although older 

 animals are not exempt. It is most common in the spring and sum- 

 mer season, particularly if the animals have been reduced by bad 

 keeping and scanty fdod during a long and severe winter, and are 

 turned upon rich pastures where they gain rapidly in flesh from an 

 abundance of good food. It usually attacks first the thriftiest and 

 most promising animal of the herd. It develops and kills its victim 

 so quickly that often the first indication the owner has of any trouble 

 is to find the finest of the flock dead in the field. If noticed in life 

 the following symptoms would be observed: A vague and listless ex- 



Eression; ears drooping; pulse irregular, feeble, and rapid; mouth 

 ot and dry; conjunctiva (lining membrane of the eye) very red from 

 congestion of the membrane; halting on one limb; stiffness, and ex- 

 cessive tenderness of some parts of the skin. Very^oon swellings 

 appear upon the loins, back, neck, head, brisket, or upon one or more 

 of the limbs. These swellings become firm and tense, with yellow 

 or bloody liquid oozing from the surface, and crepitate (crackle) 

 when pressed. Later they become insensible and even cold, and may 

 finally slough open, leaving large, unsightly, and inactive sores. 



The animal shows an unwillingness to move about, remains by 

 itself away from the rest of the herd, and if it lies down is unable 

 to rise. The appetite is entirely lost, rumination suspended, bowels 

 inactive or torpid, urine scanty and high colored, sometimes dark or 

 coffee colored. The animal losses strength rapidly, maintains the 

 recumbent position, is unconscious, eyes protruding and sightless, 

 and dies in coma, or from sheer exhaustion often within twelve hours 

 after the first manifestation oi; lameness. 



The swellings under the skin contain serum and extravasated blood 

 that decompose quickly after death, forming gases that puff out the 

 skin and give the body a bloated appearance, hastening putrefaction. 

 Black exudations of blood form extensive patches, which may be 

 confined to one limb or quarter. Similar exudations occur between 

 muscles that are gangrenous, and the blood vessels in that region are 

 full and rigid, though the blood is dark and fluid. The lungs are con- 

 gested, the lowest being the worst; frothy mucus almost fills the 

 bronchial tubes, and extensive ecchyrnosis (blood stains) covers the 

 serous membranes. The heart is soft and flabby, and filled with blood 

 that is black and semi-fluid. The rigor mortis is very slight, and 

 observed only immediately after death. 



In some cases there are premonitory symptoms of some disease be- 

 fore the aggravated symptoms are developed. Thus, in a herd where 

 one or more deaths trom black leg have occurred, others are found 

 which are not doing well, are hide-bound, the skin looks unthrifty 

 and is covered with scurf and a rough, staring coat of hair. All 

 the movements are made stiffly with arched back, and with apparent 

 effort or even pain. There is a capricious appetite, irregular rumi- 

 nation and bowels, and the urine scanty and high colored. 

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