. Poultry production. Poultry. THE INCUBATION OF THE EGG 171 the chick commences to pip the shell and the lungs and kidneys of the chick commence to function. It is the veins of this allantois which are seen radiating from the embryo at the first testing, about the seventh day of incubation, and which may be noted plainly at the second testing, about the fourteenth day. As soon as the chick pips the shell, pulmonary circulation starts and the allantois ceases to function, begins to degenerate, and is left behind in the shell when the chick hatches. Fig. 83. Appearance of a chick embryo after t
. Poultry production. Poultry. THE INCUBATION OF THE EGG 171 the chick commences to pip the shell and the lungs and kidneys of the chick commence to function. It is the veins of this allantois which are seen radiating from the embryo at the first testing, about the seventh day of incubation, and which may be noted plainly at the second testing, about the fourteenth day. As soon as the chick pips the shell, pulmonary circulation starts and the allantois ceases to function, begins to degenerate, and is left behind in the shell when the chick hatches. Fig. 83. Appearance of a chick embryo after thirty-six hours in an incubator. (Courtesy of Kansas Experiment Station.) Up to the sixth or seventh day there is nothing about the chick embryo that would help one to distinguish it from the embryo of any other animal. At this time the legs and wings begin to take a recognizable form. The body, which has been very small in proportion to the head, begins to develop more rapidly and to assume a more proportionate size. About the tenth day the little sacs containing the feathers begin to protrude, particularly along the back of the embryo. At this time there is a chalky deposit about the mouth opening, which is the beginning of the horny beak. Upon breaking an egg, what appears to be voluntary movement may be noticed as early as the sixth Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Lippincott, William Adams, 1882-1931. Philadelphia, Lea & Febiger
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Keywords: ., bookcentury1900, bookdecade1910, bookpublishe, booksubjectpoultry
