. Bulletin - Massachusetts Agricultural Experiment Station. Agriculture -- Massachusetts. 1923 I'iZt 1520 1927 1S2» 1925 KITIHO YlAKfl CHART 1.—Effect of Inbreeding on Sexual Maturity Chart 1 shows how age at sexual maturity behaved. The fact will be noted that both inbred dams and check dams were of the same age, about 176 days, at first egg in 1923. In 1924 the age for inbred dams increased to 186 days, while the check dams increased to 197 days. In 1925 inbred dams were 193 days old and check dams were 235 days old when they laid their first egg. The daughters from the dams in the inbred gr
. Bulletin - Massachusetts Agricultural Experiment Station. Agriculture -- Massachusetts. 1923 I'iZt 1520 1927 1S2» 1925 KITIHO YlAKfl CHART 1.—Effect of Inbreeding on Sexual Maturity Chart 1 shows how age at sexual maturity behaved. The fact will be noted that both inbred dams and check dams were of the same age, about 176 days, at first egg in 1923. In 1924 the age for inbred dams increased to 186 days, while the check dams increased to 197 days. In 1925 inbred dams were 193 days old and check dams were 235 days old when they laid their first egg. The daughters from the dams in the inbred group showed a mean age of 206 days in 1923, 208 days in 1924, and 204 days in 1925. Inbreeding apparently did not affect the mean age of daughters. The check daughters of 1923 averaged 238 days; those of 1924, 254 days; and those of 1925, 189 days. Early sexual maturity in the three check daughters for 1925 came from their sire, C 7984, that came from the production-bred strain, and he transmitted the dominant genes for early maturity to his daughters. During the last three years of the experiment, when the checks were inbred and the inbred strains intercrossed, all dams and all daughters in both groups averaged 200 days or less at first egg. This places them in the class of genetically early maturing birds. On the whole, chart 1 does not indicate for this experiment that inbreeding aiTected age at sexual maturity. INBRED DAifS CHECK DAMS — DAUGHTERS — ' — • — • - CHECK DAUGKTEHS. 1926 1927 1923 192'» 1925 WATINO YEARS CHART 2.—Effect of Inbreeding on Weight at First Egg. (Weight in Pounds) 1924. 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 Massachusetts Agricultural Experiment Station. Amherst, : Massachusetts Agricultural Experiment Station, 1907-1974
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