SCREW-WORMS AND OTHER MAGGOTS. 9 



The multiplication of screw- worm flies would be enormous if car- 

 casses for their breeding were present. Careful estimates indicate 

 that as many as a million flies may be produced from the body of a 

 single cow. 



CONTROL. 



The importance of destroying carcasses of all sorts of animals can- 

 not be overestimated. If all dead animals could be burned within a 

 few days after death, trouble from screw-worms in living animals 

 would be unknown. It is realized fully that the obstacles to the 

 carrying out of this method of control are many. 



BURNING OR BURYING CARCASSES. 



The complete destruction of all dead animals hy hurning is hy far 

 the hest method of control. This not only stops the breeding of all 

 blowflies but helps to prevent the dissemination of such dangerous 

 diseases of live stock as anthrax or charbon. blackleg, and hog cholera. 



The method of burning carcasses depends to some extent upon the 

 locality. Where Avood is at hand, the expense is almost negligible. 

 It is desirable that carcasses be burnt without moving them, and in 

 cases of death from anthrax this is imperative. The simplest plan 

 is to place some wood on the ground and turn the animal over on top 

 of it, adding fuel until the carcass is completely consumed. Burning 

 can be facilitated by digging a small trench, placing the animal on 

 iron rails across it, and keeping fire beneath it. If the ground is firm, 

 the irons are not essential. A very satisfactory method where stable 

 manure is at hand is to place a large load of dry manure on top of 

 the carcass and set it afire. This burns slowW and usually the animal 

 is entirely destroyed without further attention. In some districts the 

 use of crude oil or kerosene and a small quantity of wood makes the 

 burning quick and inexpensive. It is important that the entire car- 

 cass be consumed, as a body charred on the outside will often be more 

 effective in breeding screw-worms than if it had not been burned at 

 all. Complete destruction is essential also to control disease. 



If burning is impracticable, carcasses may be buried. It is neces- 

 sary to cover the top of the maggot-infested carcasses with at least 

 2 feet of closely packed soil to prevent the escape of flies. If no 

 eggs are deposited on a dead animal it is not necessary to bury it 

 so deep, but it is desirable to cover it well to prevent dogs or other 

 animals from digging it up. The free use of quicklime on the 

 carcass before covering it will destroy some of the maggots and dis- 

 ease germs. 



106906°— 17— Bull. 857 2 



