PARASITES AND PARASITIC DISEASES OF HORSES 



35 



The sawdust acts as an insulator, but even with this precaution it is 

 desirable to use tongue-and -groove lumber in the construction of 

 manure containers in order to make them tight. Concrete boxes will 

 not serve, as the manure at the sides is chilled and there is not heating 

 enough to destroy parasites. 



For practical purposes manure which has been kept in such con- 

 tainers for at least 2 weeks may be considered free from living eggs 



Figure 23. — A, Box with double walls and double floor for sterilizing horse manure; 

 B, tight-fitting lid. The space between walls and floor must be filled with 

 sawdust to insure insulation. 



and larvae of parasites and may be safely spread on pastures. Several 

 manure boxes constructed on the above principles have been in opera- 

 tion at the Beltsville station of the Bureau of Animal Industry with 

 successful results. These boxes have double-walled doors to facilitate 

 the removal of the manure after it has been sterilized. 



In default of such measures, spread horse manure on fields which 

 are to be pastured by animals other than horses, or plow it under. 



