332 DISEASES OF CATTLE. 



used several times a day until incrustation is well established. Then 

 use creoliu, 1 ounce to a pint of sweet oil, or the benzoated oxide of 

 zinc ointment, giving the affected surfaces a thorough application once 

 a day. When the eczema is not the result of an external irritant it 

 takes usually from one to two weeks before the healing is completed. 



In chronic eczema, where there is a succession of scabs or scales, 

 indolent sores or fissures, the white precipitate ointment, nitrate of mer- 

 cury ointment, or blue ointment, mixed with equal parts of cosmoline 

 or fresh lard, may be applied every second day, taking care to protect 

 the parts so anointed that the animal can not lick it off. 



In some cases the use of the following mixture will do well : Oil of tar 

 one-half ounce, glycerine 1 ounce, alcohol 1 pint. Bub this in after 

 cleansing the parts with warm water and soap. The internal admin- 

 istration of arsenic often yields excellent results in chronic eczema. 

 Take 1 dram of arsenic, 1 dram of carbonate of potash, 1 pint of boiling 

 water, and give 1 ounce of this twice a day in water, after feeding. 



IMPETIGO LARVALIS AND LABIALIS. 



Impetigo is an inflammatory disease of the skin, characterized by the 

 formation of distinct pustules, about the size of a pea or bean, unat- 

 tended by itching. The pustules develop from the papular layer of the 

 skin, and contain a yellowish white pus. After reaching maturity they 

 remain stationary for a few days, then they disappear by absorption 

 and dry up into crusts. Later the crusts drop off, leaving upon the skin 

 a red spot which soon disappears. Occasionally the crusts remain 

 firmly adherent for a long time, or they may be raised up and loosened 

 by the formation of matter underneath. The dry crusts usually have a 

 brown or black appearance. 



Causes. Impetigo larvalis generally affects sucking calves only, in 

 which the disease appears upon the lips, nostrils, and face. It is attribu- 

 ted to some irritant substance contained in the mother's milk. Impet- 

 igo labialis et facialis generally is witnessed among grazing animals, 

 regardless of age, and it especially attacks animals with white hair and 

 skin. The mouth, face, and limbs become covered with pustules, which 

 may rupture in a few hours, followed by rapid and successive incrusta- 

 tions; the scabs frequently coalesce, covering a lai*g - e surface; pus may 

 form under them, and the whole thickness of the skin become involved 

 in the morbid process. This form of the disease is attributed to the 

 local irritant properties of plants growing in the pasture, such as St. 

 John's wort (Hypcrlcum perforatumj, smartweed (Polygonutn liydro- 

 pipcr), vetches, honeydew, etc. Buckwheat, at the time the seeds 

 become ripe, is said to have caused it, also bedding with buckwheat 

 straw. 



Treatment. Sucking calves should be removed from the mother, and 

 the latter should have a purgative to divert the poisonous substance 

 secreted with the milk. When the more formidable disease among 



