296 POULTRY CULTURE 



sleeping quarters without developing roupy symptoms, and sometimes the 

 most thrifty birds will contract roup in a virulent form under such conditions. 1 

 While not as general as it was a few years ago, it is still too much the practice 

 to begin, with the first chill and frosty nights, to close poultry houses tight. 

 Under no circumstances should a poultry house be closed, more than it has 

 been during the summer, before water will freeze in it at a few feet from the 

 door. This applies to all kinds of poultry. After such degree of cold is passed, 

 windows and doors may be partially closed for birds with large, tender combs, 

 but except in the coldest sections this is not necessary, as far as the hens are 

 concerned. The open house, for the reasons stated in Chapter IX, usually gives 

 the more uniform temperature conditions and insures greater regularity of life. 



Constitution. If pullets are physically and sexually mature, well 

 nourished at the outset and well fed, and if irregularities are 

 avoided, they should, if they begin to lay about the first of October 

 and later, continue to lay steadily, and the rate of production for the 

 individual should be as high then as at any time. To a very great 

 extent the low averages for flocks at this time result from the pres- 

 ence of pullets that are not laying. After a few weeks of laying, 

 differences in constitutional vitality begin to become apparent. 

 Some birds slow up or stop, and perhaps show loss of weight ; 

 others continue the same rate of laying without noticeable loss of 

 weight, and perhaps with some gain in weight. .Differences due to 

 constitutional vitality are most marked when comparisons can be 

 made between selected lots. Unless birds are very deficient in 

 vitality, the lack of it need not seriously affect the egg yield dur- 

 ing the first winter. Good care and an abundance of stimulating 

 food will keep up egg production, though it may shorten the 

 productive life of the bird. 



Exercise affects egg production only through its effects on the 

 general health and condition of the bird. Hens will lay and lay 

 well for many months at a stretch with very little exercise, but 

 eventually the lack of exercise will tell. The effects are not in all 

 cases the same. Perhaps the most common development is a 

 gradual softening and weakening of the entire system, most pro- 

 nounced at first in its effects on the digestive system. Under ordi- 

 nary feeding hens are likely to lose weight ; under very heavy 



1 It is probable that in such cases the germs of roup are present either in the 

 houses or in the birds, which were practically immune under good hygienic con- 

 ditions. That is a point not easily determined in ordinary instances of this kind. 



