26 TJie Business Hen. 



normal eggs in each case being laid a few days after the abnormal. The 

 abnormality, however, may continue. One hen laid seven diminutive 

 tggs continuously and then stopped laying. Of the five eggs marked (a), 

 Fig. 10, the first two eggs which are perfect and normal were followed by 

 the abnormal long-drawn-out egg which was so weak at the point that 

 it scarcely retained the egg contents. Within two or three days follow- 

 ing the other two eggs were laid which were perfectly normal and sound. 



Just how long it takes for each part of the egg to be secreted is 

 not known. The whole process is supposed to take about 18 hours. Con- 

 siderable time is taken for the shell to be deposited and to harden. Two 

 eggs can be under way at the same time. When the hen is not laying the 

 oviduct is shrunken and not more than one-fifth its natural size. Like all 

 secretory glands, the oviduct enlarges with the activity of the organ. In 

 this one respect it may be compared with the udder of a cow "fresh in 

 milk" and one "gone dry." The oviduct when stretched out and congested 

 is normally a little over 20 inches long. 



The development of an egg is more elaborate and more exhaustive than 

 a simple secretion like that of milk-making. It is both a reproductive and 

 a secretory process. The perfect egg contains the materials and the life 

 to form a new animal, a shell to protect it during subsequent develop- 

 ment, and the food to nourish it for several days after it is born. A good 

 hen is expected to lay, that is, to give birth to, about 150 offspring in a 

 year, which is equivalent to about five times her own weight. This is 

 a heavy drain upon her system. Something of its immediate effect will 

 be seen by the fact ascertained by one of our students (Henry Jennings) 

 that a hen's temperature immediately after laying is from two to three 

 degrees higher than normal, the normal being about 106. 



The composition of the egg remains practically constant. This is 

 true even under different systems of feeding. Careful observation of two 

 pens of Plymouth Rock hens was made and the eggs analyzed after 

 they had been fed about three months on radically different rations. 

 Pen one was fed largely on protein-rich foods; pen two was fed largely 

 on foods deficient in protein, the former being a ration for making muscle 

 and the latter for making fat. Nevertheless the eggs from the two pens 

 remained practically identical in composition. This illustrates one of the 

 highest laws of nature, namely, that the animal will sacrifice its own bodily 

 strength in order to make a perfect offspring, which is a necessary pro- 

 vision to insure the perpetuation of the species. There is little difference 

 in the composition of eggs from different breeds, or between light-shelled 

 and dark-shelled eggs. 



There is a difference between hens that are well fed and those that 

 are improperly fed, as shown in their fertility, the strength of the germs 

 and the vitality of the chickens. The chemist may not be able to find it 



