16 Georgia State College of Agriculture 



by the formation of a lump or tumor above which will be found a 

 small hole in the skin. Through this opening the parasite obtains its 

 air supply, the hole becoming larger with the growth of the larva. 

 The larval stage of development is ten months. When the larval 

 development is complete the grub passes out through the opening in 

 the skin and drops to the ground. Then, an earthy cocoon forms 

 around it and it lies dormant for a time, finally emerging as a fully 

 developed adult fly. 



The losses occasioned are severe. Loss is caused by the irrita- 

 tion of the cattle during the egg-laying season, interfering with 

 the animal's grazing by the constant irritation of the skin and flesh 

 in the region of the back, by the lessening of milk production in 

 infested cows, by the loss of flesh in cattle butchered during the 

 time the grubs are present and by the great loss in reduction of the 

 value of the hides of infested cattle. 



Treatment and Control. As this parasite passes the winter 

 months in the larval form under the animal's skin, it may be con- 

 trolled by destroying the larvae during these months. Press out 

 the grub and kill it by crushing or burning or inject gasoline in 

 small quantities into the openings in the skin. Kerosene may also 

 be used for the same purpose. 



As a fly repellant for use during summer the application of a 

 mixture consisting of three parts of fish oil and one part of kero- 

 sene is recommended. 



Lice. 



Three species of lice infest cattle. Two of these suck blood and 

 the other is flesh-eating. They are the broad-nosed ox louse, Hema- 

 topinus Eurysternus; the long-nosed ox louse, Hematopinus Vitula; 

 and the biting louse, Trichodectes scalaris, or red louse. The first 

 two species are blue in color and are much more injurious than the 

 latter. 



Treatment. Infested cattle and calves should be dipped or spray- 

 ed with a solution of coal tar dip or disinfectant. During winter 

 and early spring lice infestation is much more common than dur- 

 ing the remainder of the year. Treatment for the destruction of 

 lice should be regularly applied, spring and fall, and at such other 

 times as may be necessary. Two per cent solution of cresol disin- 

 fectant in dipping vat or spray application is the thing necessary. 

 In case only a few animals are to be treated application by hand 

 may be practiced. A mixture of two parts of kerosene and one 

 part of lard makes an efficient local application. 



INTERNAL PARASITES. 



Stomach Worms (Haemonchus contortus), (Strongylus contortus). 

 These are hair-like worms about one inch long, blood suck- 



