PARASITES AXD PARASITIC DISEASES OF HORSES 



41 



vantage of this method of treatment is that it can be used when the 

 weather is too eold for dipping. The disadvantages are that it is 

 necessary to have a gastight inclosure and the animal's eyes and 



Figure 26. — Fumigation with sulfur gas for lice. Eyes and nostrils must be kept 

 away from the gas. Part of head not fumigated must be hand treated. 



nostrils must be kept away from the gas. A concentration of about 

 1 percent sulfur dioxide is necessary to kill the parasites, and serious 

 injury or death may result if the gas comes in contact with the eyes 

 or nostrils. After fumigation it is necessary to hand treat that port 

 of the head that was not fumigated (fig. 26). 



