THE EGG AND ITS GERM 



A PRACTICAL STUDY OF EGGS 



A NON-TECHNICAL PRESENTATION OF THE FORMATION AND PRODUCTION 

 OF EGGS— THE CAUSE OF DOUBLE-YOLKED, SOFT-SHELL EGGS AND CROOK- 

 ED EGGS, ONE EGG WITHIN ANOTHER, ROTTEN NEW-LAID EGGS, ETC. 



G. BRADSHAW 



LTHOUGH eggs are a common article of food 

 there is not a general knowledge amongst poul- 

 trymen as to their formation. The shell or 

 envelope • is white or colored according to the 

 breed which produces it, and is composed of 

 carbonate of lime, phosphate of lime, and animal 

 gluten; salts of lime causing the particles to ad- 

 here. Soft eggs are either eggs without a shell, 

 or the shell may be so thin as to feel soft through the deficiency 

 of salts of lime. It is a matter of surprise where a hen finds 

 all the lime necessary, for if she lays 150 normal sized eggs in 

 the year she will have produced two pounds of pure carbonate 

 of lime. 



HENS ARE WONDERFUL CHALK MAKERS 



Mr. P. L. Simmonds F. L. Z., on this subject in the Journal 

 of the Society of Arts, says: — "If a farmer has a flock of 100 

 hens, they produce in egg shells about 137 pounds of chalk an- 

 nually, and yet not a pound of the substance, or perhaps not 

 even an ounce may be found on the farm. The materials for 

 the manufacture are found in the food consumed, and in sand, 

 pebbles, brickdust, pieces of bone, etc., which hens and other 

 birds are continually picking from the earth. Their instinct 

 is keen for these apparently innutritions and refractory sub- 

 stances, and they are devoured with as eager a relish as the 

 cereal grains or insects." 



If hens are confined to barns or outbuildings, it is obvious 

 that thejegg-producing machinery cannot be kept long in action, 

 unless materials for the shell are supplied in ample abundance. 

 If fowls are confined in a room and fed with any of the cereal 

 grains, excluding all sand, dust or earthy matter, they will go 

 on for a time, and lay eggs, each one having a perfect shell made 

 up of the same calcareous elements. 



THE SHELL IS A "SIEVE" 



The shell is porous to such an extent that when examined 



by a microscope it has quite a sieve-like appearance, and is 

 permeable by the air, otherwise the chicken could not live dur- 

 ing the incubating period. 



This porosity of the shell, although absolutely necessary 

 when the eggs are to be incubated, is detrimental when such 

 have to be used as an article of food from the fact that by means 

 of these minute perforations there is a continual evaporation, 

 so that from the time the eggs are laid until consumed there is 

 a wasting and deterioration of the contents, the extent of which 

 is dependent on the temperature and other conditions under 

 which they are kept, it being very well known that eggs deter- 

 iorate much quicker in summer than in winter. 



FORMATION AND PRODUCTION OF AN EGG 



Anyone, upon opening after death the body of a hen, will 

 find a cluster of eggs in formation much like a bunch of grapes, 

 and called the ovarium (see illustration.) These, however, 

 are but rudimentary eggs, and I have counted as many as sev- 

 enty in one bunch, and are in size from a pin's head to the full- 

 sized yolk of an egg. Each of the eggs is contained within a 

 thin transparent sac and attached by a narrow pipe or stem to 

 the ovary, and during the laying period of the hen these eggs 

 are maturing and thus keeping up the supply which she lays. 



These rudimentary eggs have neither shell nor white, con- 

 sisting wholly of yolk, on which floats the germ of the future 

 chicken; and as they become larger and larger they arrive at 

 a certain stage when, by their own volition, weight, or other 

 cause, they become individually detached from the bunch and 

 fall into a sort of funnel leading into a pipe or passage called 

 the oviduct — this organ in the hen being from 22 to 26 inches 

 long. 



THE COATING OF ALBUMEN 



During the passage of this egg or ovum to the outer world 

 it becomes coated with successive layers of albumen-^the 

 white — which is secreted from the blood-vessels of the oviduct 



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