. Poultry production. Poultry. BREEDINO 139 The reason for this appears to lie in the fact that hens produce two kinds of ova, one of which always produces males when fertilized, while the other produces females. The male produces only one kind of sperm so far as sex is concerned, and these all carry the factor for barring. The female-producing ova never carry the barring factor, while the male-producing ova always do. The only result possible is that the male inherits light barring from both his sire and dam, while, the female inherits it only from her sire. Fig. 69. Showing the difference in
. Poultry production. Poultry. BREEDINO 139 The reason for this appears to lie in the fact that hens produce two kinds of ova, one of which always produces males when fertilized, while the other produces females. The male produces only one kind of sperm so far as sex is concerned, and these all carry the factor for barring. The female-producing ova never carry the barring factor, while the male-producing ova always do. The only result possible is that the male inherits light barring from both his sire and dam, while, the female inherits it only from her sire. Fig. 69. Showing the difference in barring of Plymouth Rocks that are full brother and sister. (Courtesy of Kansas Experiment Station.) This may be illustrated as follows: Let X represent an ovum that will produce a male when fertilized by a spermatozoon, which may also be designated by X. Let 0 represent an ovum that will produce a female when fertilized. That is to say, offspring having the constitution XX will be males, while those represented as XO will be females. X always carries a factor for light barring, while 0 never carries such a factor. The mating of a pair of Barred Plymouth Rocks may be represented as follows, if B is allowed to represent the barring 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
