Q44 BLACK LEG 
Symptoms. The symptoms generally are those of a bacteriemia. 
Arloing, Cornevin and Thomas state that general symptoms always 
precede the local manifestations. Nérgaard reports finding cattle 
with marked local lesions but few of them suffering from general 
symptoms, although the latter may have preceded the former and 
have subsided. 
There is elevation of temperature, reaching in some cases 107° F. 
It usually falls to the normal or even subnormal before death. There 
is loss of appetite, loss of rumination and pronounced depression. 
Respiration is accelerated. The animal moves with difficulty and lies: 
down frequently. At first the visible mucous membranes are con- 
gested and within twelve to fifteen hours they have a dirty leaden or 
purplish color. 
The local symptoms may appear on different parts of the body 
except below the knee or hock joints and on the tail. They are less 
frequently found about the head, although they may appear in 
angles of the jaws and throat. They are more frequent on the thighs, 
neck, shoulders and lower region of the chest. The swelling is at first 
small and painful. It spreads rapidly and may in a few hours attain 
to a large size, when it becomes characterized by a crackling and a 
gurgling sound when the hand is passed over it. On percussion it 
gives a clear, tympanic sound due to the collection of gas in the 
affected tissues. At the center of the larger swellings the skin 
becomes dry and parchment-like, cool to the touch and painless upon 
pressure. If lanced, a dark, reddish, frothy fluid flows from the 
wound. It emits a disagreeable odor. In some cases there is but 
one swelling but usually there are two or more which may become 
confluent. The lymph glands adjacent to the swellings are much 
enlarged. There is usually trembling of the muscles, which, as death 
approaches, may develop into violent convulsions. 
Hun has pointed out the interesting fact that in a very large per- 
centage of cases the swellings appear on the right side. There seems 
to be no explanation given for this localization. In this country, 
records are wanting of observations on this point. Hoopen has called 
attention to the characteristic sour odor from the mouth. 
Arloing has called attention to a mild form of this disease in which 
the symptoms are slight debility, loss of appetite and slight local 
swelling. 
The duration of the disease is from several hours to three days. 
Occasionally it is longer. . The prognosis is grave. 
