328 DISEASES OF CATTLE. 



ELEPHANTIASIS (SCLERODERMA). 



This condition consists in a chronic thickening of the skin, which 

 may effect one or more limbs or involve the whole integument. It is 

 characterized by recurrent attacks of swelling of the skin and sub- 

 cutaneous areolar tissue. After each attack the affected parts remain 

 infiltrated to a larger extent than before, mitil finally the skin may 

 attain a thickness of an inch, becoming wrinkled and fissured. In 

 cattle this disease is confined to hot climates. The predisposing 

 cause is unknown. 



EDEMA (ANASARCA OF THE SKIN). 



This is a dropsical condition of the skin and snbcutanetms areolar 

 tissue, characterized by pitting under pressure, the fingers leaving a 

 dent which remains a short time. 



Causes. — Edema generally results from a weakened state of the sys- 

 tem arising from previous disease. It wvAy also be dependent upon 

 a functional derangement of the kidneys, upon weak circulation, or 

 obstruction to the flow of blood through the lungs. In debilitated 

 animals and in some animals highly infested with parasites there is 

 swelling of the dewlap or of the fold of the skin between the jaws. 



Symptoms. — Painless sAvelling of a limb, udder, loAA-er surface of 

 abdomen, or lower jaAv becomes apparent. This may increase in 

 dimensions for several days or may attain its maximum in less than 

 24 hours. Unless complicated with some acute disease of a specific 

 character, there is not much, if any, constitutional disturbance. The 

 deep layer of the sldn is infiltrated with serum, which gives it the 

 characteristic condition of pitting under pressure. 



Treatment. — When the cause can be ascertained and removed we 

 may expect to see the edema disappear. "^^Tien no direct specific 

 cause can be discoA'ered and the animal is debilitated, give general 

 tonic. If, on the contrary, it is in good flesh, give a purgative, fol- 

 lowed by half an ounce of acetate of potassium twice a da}^ Ex- 

 ternal applications are useless. 



Edema may be distinguished from erysi})elas or anthrax l)y the 

 absence of pain and fever. 



DERMOID AND SEBACEOUS CYSTS (WENS). 



A dermoid cyst is formed by an involution of the skin with a 

 growth of hair on the inner wall of the sac. It may become embedded 

 deeply in the subcutaneous tissues or may just penetrate the thickness 

 of the skin, where it is movable and painless. They are generally 

 found within the ear or at its base, although they may form on any 

 part of the body. Usually they have a small opening, from which a 

 thick, cheesy matter can be squeezed out. The rational treatment is 

 to dissect them out. 



