. Cyclopedia of farm animals. Domestic animals; Animal products. 530 POULTRY POULTRY In the chart, a dotted line represents female blood (egg), and a full line male blood (sperm); the circle at the union of two such lines indicates the prog- eny of the union of the egg and the sperm. In the third filial generation, whose blood is derived equally from the two parents, No. 10 constitutes a strain distinct from No. 8, which has thirteen-sixteenths blood of the original hen, and from No. 12, which has the same proportion of the original cock. From these three strains, by proper manipulation addi-
. Cyclopedia of farm animals. Domestic animals; Animal products. 530 POULTRY POULTRY In the chart, a dotted line represents female blood (egg), and a full line male blood (sperm); the circle at the union of two such lines indicates the prog- eny of the union of the egg and the sperm. In the third filial generation, whose blood is derived equally from the two parents, No. 10 constitutes a strain distinct from No. 8, which has thirteen-sixteenths blood of the original hen, and from No. 12, which has the same proportion of the original cock. From these three strains, by proper manipulation addi- tional strains may become established. The methods employed for attaining an ideal are of two general sorts, depending on the end sought. If it is desired merely to improve a quality already present, the method of selection is employed. If, on the other hand, it is desired to add a new char- acteristic to a given breed or to combine the char- acteristics of one or more breeds, then hybridization is necessary. Selection involves the careful inspection of the individuals of any generation, and the preservation for breeding of only the best. Let it be required to improve the egg-yield of a given strain : study the egg records of the yearling hens, and preserve for breeding the progeny of the best. Let it be required to increase the rate of growth : keep and study growth records, and save the fastest growers for breeders. Even those who do not keep records make a selection, as the breeding season approaches, of the most vigorous cocks and the shapeliest hens, and this rough selection helps to maintain the strain at a high standard of general excellence. A more rigorous selection and selection for particular points often involves measurements, weighing, and the like, and pedigree breeding, of the methods of which something will be said in a later paragraph. Hybridization involves the crossing of two strains, varieties, or races in order to combine the favor- able qualities of the tw
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Keywords: ., bookauthorbaileylh, bookcentury1900, bookdecade1920, bookyear1922
