THE HEN'S EGG.

Marlborough Express, Volume XLI, Issue 71, 25 March 1907, Page 2

THE HEN'S EGG.

HOW IT IS FORMED

At this time of the year when poultry keepers will find their pullets commencing to lay, it will be opportune to give a few points regarding the formation of the egg, and the conditions which are best for egg production. Frequently we find young pullets become egg-bound mainly through improper feeding, so that the points given below will be timely and should prove valuable to our readers. 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 ovarimn. Frequently there are as many as 70 in one bunch, varying in size from a pin's head to the full-sized egg. Each of these eggs is enclosed in a thin transparent sac, and attached by a narrow pipe or stem to the ovary. During the laying period of the hen these eggs are maturing, and thus keeping up the supply. These * rudimentary eggs have neither shell nor white, consisting wholly of yolk, oh which floats the germ o.f the future chicken. As they become larger and larger they arrive aba stage when, by their own volition, weight or from other cause, they become individually detached from the bunch, "and fall.into a sort of tunnel, leading into a pipe,or passage way called the viaduct, this organ in the hen being from 22 to 26 inches long. During the passage of .this egg, or ovium, to the outer world it becomes coated with successive layers of albumen—the white—which is secreted

from the blood vessels of the'oviduct in the form of a thick, glareyfluid,. and is prevented from mixing with the yolk by the membrane or sac which surrounded the latter before it became detached from the cluster. It is also strengthened by a second and stronger membrane, formed around the yolk immediately falling into the funnel, and having what is like two twisted cords of .a more dense albuminous ■character called by anatomists, chalazes. These pass quite through the

white at the ends, and are, as it were, •embedded therein, these preventing the yolk and germ from rolling attout when the egg is moved and serving to keep the germ uppermost, so that it may best receive the heat imparted during incubation. It is during the passage of the egg through the lower part of the oviduct that it gets covered with the two skins that are found inside the shell. These, although lying close around the

egg, at the thick end become separate and form what is called the air bubble »or chamber. This speck or -air space

daily becomes larger as the egg gets older, and is frequently equal to onefourth of the entire egg. This air

. chamber, if perforated with the finest needle, will prevent the egg from Hatching. When the egg has advanced more than half .way down the oviduct, it is still destitute of shell, which begins to be formed by a process of secretion, and, when about completed, the various shades of brown and tinted colouring matter are imparted in those bvoeds Lo vrliioh coloured eggs are peculiar. Sometimes, in very brown eggs, white spots appear, but these can readily be rubbed off. "Wlien t\e shell and colouring are complete the egg continues to advance along the oviduct until the hen goes to nest and lays it. Eggs are produced from the surplus food, says an American authority, which is that over and above what is required for the sustenance of the hen. If this is too stimulating, or given in excessive quantities, the result is that in tlio former ease the ova are prod iced, so-rapidly that sometiixes two of ilt'.Mvs drop hvto.the oviduct together, which results in the. eccentricities which frequently puzzle -the poultry keeper. The ova travel together along the passage and receive the white separately, but become enveloped in one shell," and when laid are commonly known as double-yolked eggs. More properly it is a double egg, the white being duplicated as well as the yolk. Should these yolks be fertilised and the egg hatch we get "he occasional four-legged chicken, or other monstrosity.

A further result of stimulating food Is varied, from the above when the ova mature in excess of one a day. - In place of falling into the passage in pairs, as above, the two drop separately but on the same day. This results, in soft eggs, not from the want of shell-forming material, but rather because the shells cannot be formed as fast as the mature egg is ready for the covering.

Crooked eggs are no uncommon things in the poultry yards, and are attributable as folloavs : —Twenty-four hours are usually sufficient for the.

formation, of a perfect shell, but from stimulation a second ovum falls after its predecessor, reaching it before laid; the second egg, which is up to this time soft and is lying against the hard one, becomes covered with a shell. When laid it presents a flat or crooked side, the result of its position against the hard one.

To overfeeding is also attributable "the further irregularity of one perfect ege being formed within another, and caused by irritation of the oviduct, which, contracting in .front of the .perfectly formed egg, instead of behind it,' forces it back until it meets another yolk, when the two join and again become coated with the

white and the shell, thus producing another wonder. ■■' Other abnormalities are found in form of small eggs. Sometimes when the ova are nearly exhausted by continuous laying, the secreting organs may be most active, which results in small, marble-sized, but perfect-look-ing eggs, which are merely a shell covering a portion of albumen. Such "eggs" when laid.have the peculiarity of never having been at any>tage attached to the ovary ,but are a product only of the oviduct. To the eternal fatness of a hen is due other eccentricities than those mentioned, including the apparently paradoxical feat of laying stale newlaid eggs, this being a not infrequent occurrence. The egg. br-ina; unable to iorce its way through the fatty oviduct, is retained two ov three 7 days near tho mouth of th is orpan and 'if fertilised, the heat of tha'hen's body tends to putrefy it. Whor, ultimately laid it is in addled condition.

To other causes, but principally to diseased organs, is ih'<p. a departure from the normal in t-lu> way of colour. •A hen that lays white or lirown eggs', on rare occasions produces one almost black, while at other tiim;:? these vagaries much resemble 4hp dark green °l th? emu's eggs. T>; mn^t instances the shells are rough, vpy--, corrugated, or otherwise ir/-<-i^fr. Then there are the instances of ■Wivrngn matter being found in rv.v^. c'l.-.^ of blood being nothing unnsuu!. This is the result of the breaki^ •>> » 1,-lood vessel internally, and, fj#iin. p^mhlj the enect of overfeeding.