. The book of poultry. Poultry. §2 STANDARD-BRED POULTRY 67 Suppose, now, that a pair of blacks and a pair of whites are mated in every possible way. Mating black with black gives bj—a pure black like its parents, if the strain is fully established. Mating the black female with the white male gives bi w^. Mating the white female with the black male gives b^ Wi. Finally, the white pair produces wt. The process is shown by the diagram of Fig. 2. If sex counts for any- thing, the crosses 6i w^ and b^ Wi should show it, for the cross 6, w' h'w. h w, (1) 6| (5) 6| w^ (9)b^w^ (13) b\w\ (2)b^w^ (6)b^
. The book of poultry. Poultry. §2 STANDARD-BRED POULTRY 67 Suppose, now, that a pair of blacks and a pair of whites are mated in every possible way. Mating black with black gives bj—a pure black like its parents, if the strain is fully established. Mating the black female with the white male gives bi w^. Mating the white female with the black male gives b^ Wi. Finally, the white pair produces wt. The process is shown by the diagram of Fig. 2. If sex counts for any- thing, the crosses 6i w^ and b^ Wi should show it, for the cross 6, w' h'w. h w, (1) 6| (5) 6| w^ (9)b^w^ (13) b\w\ (2)b^w^ (6)b^w^ (I0jb\w\ (7)b\w\ (IDb^w^ (4)b\w?| (8)b^ wj (W)b^ w (U)b^w^ (M)b^w^ (16) w% of b^ Wi has for its an- cestors a black male and a white female; the cross bi w^ descends from a black female and a white male, the sexes being reversed. The next step, as shown in the diagram (3) bf w^ of Fig. 3, may consist in crossing the hy- brids 6i w^ and b^ Wi, or the entire output of the first mating may be crossed in every possible way. The combination of the cross will be shown first. The cross 62 w^, nimibered (1) shows two black females and two white males as the ancestors. Mating 61 w^ with b^ Wi gives b\ w{, numbered (^), in which both sex and color are equal. Mating b^ Wi on the right below with bi w^ on the left above gives b-} w\, num- bered (3). Finally, b^ Wi on the right below with the same cross on the right above gives b^W2, which is numbered (4). This cross reverses the sexes shown in(l). The diagram shows the entire operation. It will be noticed that for the first time both the sexes and colors are evenly balanced in (2) and (3).. 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 McGrew, Thomas Fletcher, 1850-1930. New York, The Macmillan Company
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectpoultry, bookyear1921
