THE ANIMAL PAKASITES OF CATTLE. 



501 



m- 



agaiust 



The blue lice (figs. 9, 10) suck the blood of cattle and are more 

 injurious than the red lice (fig. 11). Unless very abundant the latter 

 cause little injury. If numerous they irritate and 

 worry their host probably more by their sharp 

 claws than by their bites, as their food seems to 

 consist entirely of particles of hair and dead skin. 

 Cattle lice reproduce by means of eggs or nits 

 (fig. 12) which they fasten to the hair. The blue 

 lice infest chiefly the neck and shoulders; red lice, 

 when present, may be found almost anywhere on 



the body, but are usually 



most numerous on neck, 



shoulders, and at the root 



of the tail. 



On account of the itch- 

 ing due to the lice, 



fested cattle rub 



posts, trees, etc. , and lick 



themselves, the hair some- 

 times coming out and the skin becoming 



thickened so that mange may be suspected. 

 Treatment for 



lice. — Cattle in fested 



with lice should be 



dipped in the spring 



and again in the fall, 

 using a coal-tar or tobacco dip, or Beaumont 

 oil emulsion (see p. 504). If only a few cattle 

 are to be treated the dip may be applied with 

 a brush or cloth, or with a small spray pump, 

 or a mixture of kerosene one-half pint and 



lard 1 pound may be 



smeared on the body. 



MANGE, ITCH, SCAB. ffl 



Fig. 9. — Short-nosed blue 

 louse (IliBmatopinus 

 eurysternus) of cattle. 

 (From Bureau of Ento- 

 mology.) 



Fig. 10.— Long-nosed blue louse 

 (Hxmatopinus vituli) of cattle. 

 (From Bureau of Entomology.) 



w 



Fig. 12 — Egg of short-nosed blue 

 louse (Hcematopinus eurysternus) 

 attached to a hair. (From Bu- 

 reau of Entomology.) 



Cattle are subject 

 to four kinds of 

 mange, of which 

 common mange or 

 psoroptic mange is 

 the most important. 



Psoroptic mange of cattle is caused by a 

 species of small mites (fig. 13) which multi- 



Fig. 11.— Red louse (Trichodectes 

 scalaris) of cattle. (From Bu- 

 reau of Entomology.) 



"For a fuller discussion see Farmers' Bulletin 152, issued by the United States 

 Department of Agriculture. 



