HOUSING AND HYGIENE 



295 



Stewart and Atwood* found that when all other conditions 

 were as equal as it was possible to make them, eggs from 

 Leghorn hens on free range gave a fertility of 91.5 per cent., 

 while eggs from those confined in yards 15 by 100 feet gave 

 a fertility of 75.6 per cent. At the same time, 83 per cent, 

 of the fertile eggs from hens on free range hatched, while 

 but 67.5 per cent, of the fertile eggs from the yarded hens 

 hatched. Bushnell and Maurer^ found that range, as com- 

 pared with close confinement, makes a decided difference 

 in the bacterial content of the eggs laid, even when the 

 rations fed are the same. Whether the difference was due to 



North yards are frequently piled high with snow while the birds are dusting 

 themselves to the south of the house. 



the increase in exercise or the green feed and insects it was 

 impossible to determine, but when hens were given free range 

 on April 20 there was a marked falling off in the bacterial 

 content of the eggs. This change was not due to seasonal 

 variation, as summer eggs usually showed more than 10 per 

 cent, greater infection than spring eggs. 



When circumstances make it necessary to yard the stock 

 the yards should be as large as possible and provision made 

 for double yarding. By double yarding, reference is made to 

 the practice of keeping the stock in one yard while a crop is 



' West Virginia Bulletin. 



^ Unpublished data, Kansas Experiment Station. 



