438 MARKETING THE PRODUCTS. . 
fertile eggs. There is probably nothing the poultryman can do 
which would so much improve the quality of eggs for table use 
as the production of infertile eggs (Figs. 198 and 199). 
A 
Photo by United States Department of Agriculture, 
Fia. 198.—A comparison showing the effect of incubation temperature on fertile and 
infertile eggs. A, Strictly fresh egg with fertile germ. B, Infertile egg after being in incu- 
bation temperature for 48 hours. The sterile germ never shows any development. C, Fertile 
germ after 48 hours of development. Eggs with sterile germs keep much longer and are 
much safer to use for human food. 
Candling.—It is evident from the above that all kinds of 
eggs are found in the egg market,—stale, shrunken, unclean, 
broken, cracked, and even rotten eggs. These conditions are 
indirectly due to one of the following causes: Carelessness on the 
poultry farm, carelessness in marketing, and climatic conditions. 
