PARASITIC DISEASES OF CATTLE. 911 



spots covered with white scales, and surrounded with bristly or split hairg 

 which are scabbed around the roots, with some eruption on the skin. 

 The microscope shows it to be a vegetable parasite. It is readily trans- 

 mitted from one animal to another. 



What to do. — Clip off the hair, and wash the part with soap and water, 

 to remove all scabs ; when dry, rub in well a little of the following : 



No. 56. 2 Ounces tincture of iodine, 



1 Ounce oil of tar, 



2 Ounces glycerine. 



Mix. 



Repeat the application once a day until cured. Or, instead, the follow- 

 ing may be used in the same way : 



No. 57. 1 Ounce solution iodo-bromide of calcium compound, 



3 Ounces water, 



Mix. 



Rub well in once a day. 



VII. Hook- Worm Disease of Cattle. 



This disease, also referred to as bovine uncinariasis and salt sickness, 

 has been reported from Texas, Florida, and South Carolina, and is prob- 

 ably widely distributed throughout the Southern States. C. F. Dawson, 

 of the Florida Station, reports it as the most common disease of cattle. 

 Investigations by A, F. Conradi and E. Barnett, at the South Carolina 

 Station, have shown cattle to be seriously infested with the hook worm, 

 which is frequently associated with other intestinal parasites, including 

 the twisted wireworm or stomach worm, the inflated bowel worm, and the 

 hair worm. The disease as described by Doctor Dawson is "an acute or 

 chronic parasitic disease manifested at first by low fever, diarrhea, loss of 

 appetite, soon becoming chronic, with continuance of low fever, constipa- 

 tion, loss of appetite, progressive emaciation, and pronounced anemia, 

 which, in many cases, terminates fatally." 



Young animals are more susceptible than older ones, but all ages may 

 be affected. The nematode or round worm, formerly described as Un- 

 cinaria radiata, is the exciting cause of the disease. These worms, found 

 principally in the duodenum or first division of the small intestine, are 

 provided with an armature of sharp teeth, by means of which they pierce 

 the lining of the intestines and suck blood, moving from place to place. 

 Other species of hook worm which affect sheep, dogs, cats, foxes, man, and 

 other animals should not be confounded vnih the species that affects cattle. 



How to know. — The adult worm is from one-half to five-eighths inch in 

 length and of the thickness of an ordinary pin. The eggs are deposited 

 in the intestinal tract and are discharged in the feces, through an examina- 

 tion of which the extent of infestation can be determined. Conradi and 

 Barnett have observed a gorged female whose oviduct contained more than 

 1,500 eggs, 17 of which were deposited in one hour. At a temperature 



