Ml62 profitable poultry production 



growth of vessels which follows the same course as 

 the blood vessels. The natural reviver of impure 

 blood is the oxygen in the air. There are no lungs 

 in the shell, but this new organ, called the allantois, 

 which lies next the shell, undertakes the work of 

 breathing. Hence the necessity for the pores in 

 the shell. If the shell were made non-porous the 

 allantois would be useless. This has been proved 

 with eggs which have had their pores filled with 

 wax. When warmth is applied in the ordinary 

 [■way, the first indication of growth appears, but the 

 germ dies simply from want of fresh air. 



WHY EXERCISE CARE IN HANDLING 



Some people test their eggs, particularly white- 

 shelled ones, on the fourth day, though a much 

 .better course is to test them on the seventh or 

 eighth day. Perhaps a caution is needed against 

 testing eggs too frequently. It is very hard for 

 a beginner to refrain from handling his eggs, but 

 knowing the delicacy of the blood vessels, which 

 form a perfect maze of tracery over the yolks, and 

 knowing that these and a further set busy absorb- 

 ing the yolk are very highly sensitive, he will per- 

 ceive that the less he interferes with the eggs the 

 less likely he is to damage this fragile and delicate 

 interior. 



Another reason for not testing frequently is that 

 in so doing the eggs are held up to the light in an 

 unnatural position and some of these organs inside 

 the egg are being twisted. Again, there is the light. 

 [To test eggs properly a very clear light is needed 

 ! to pass through the egg. Therefore eggs should 

 1 be tested only once, and that about the seventh or 



