CONTROL OF FLIES IN BARN YARDS AND PIG PENS 171 



miles or more under rural conditions, but that there is a rapid decline 

 in the number of flies which reach points two miles or more from the 

 source of production. It is also desirable that the pens be located a 

 considerable distance from main highways, as passing vehicles help to 

 disseminate the flies. 



2. Drainage. — Adequate drainage is essential. It is preferable to 

 have hog^feeding stations located on hilly ground and never on flat areas. 



3. Adequate Room. — In feeding garbage it is essential in order to 

 maintain sanitary conditions that the hogs be given a considerable 

 acreage. I would place this at a minimum of 225 sq. ft. per hog, or 

 approximately 190 hogs to the acre. Of course as a general principle in 

 fattening hogs it is considered necessary to reduce activity by close 

 penning. It has been proven, however, that hogs make satisfactory gain 

 when heavily fed if kept in large pastures. 



OP£li HOG-FEEDINC TKOUCh 



Fig. 36. — Plans of open hog-feeding trough. (Bishopp.) 



4. Feeding Troughs and Platforms.— Concrete feeding troughs and 

 platforms are essential under present inadequate labor conditions. A 

 number of forms of troughs and platforms may prove satisfactory from 

 a sanitary standpoint. In some cases feeding floors are used without any 

 troughs but this necessitates daily cleaning. Under outdoor conditions 

 such as exist in the South, it is advisable to locate the feeding troughs on 

 land with pronounced slope. A simple form of construction consists of a 

 concrete platform about 15 feet wide, length in proportion to number of 

 hogs (fig. 36). This should have a backward slope of about 10 inches. 

 The trough can be formed by setting a plank on edge in the concrete 

 about three feet from the upper side and parallel with it or by a concrete 

 ridge several inches high to form the lower edge of the trough. The 

 upper edge of the platform should be raised so as to prevent water from 

 washing into the trough and the feed racks to receive the garbage should 

 be constructed over the front edge of the trough in such a way as to 



