Proceedings of the Meetings for the Years 1908, 1909, 1910

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Halaman 41 - In two instances quite certainly, and possibly in several others, a new and distinct variation has suddenly appeared within a line and thereafter bred true, thus presenting the characteristic phenomena of mutation. The most striking instance of this sort occurred in line D61D168 and may be given here in detail. The main part of this line has already been discussed (p. 331). It will be recalled that it is a line of low fecundity. In 1908 there appeared in it one individual of distinctly higher fecundity...
Halaman 35 - In some years the selection was fortunate in getting nearly all the breeders from good (ie, "high production") genotypes or from good combinations of genes. In other years just the opposite thing happened; the high layers chosen as breeders came from low genotypes or combinations of genes. The general upshot was that while the. selection of high layers merely as such was systematic year after year the result attained in the general flock production was entirely haphazard and uncertain. This is exactly...
Halaman 33 - winter production" is a better unit for the study of the inheritance of fecundity than any other which can be used practically. All records of production given in this paper are then to be understood as "winter" records, comprising all eggs laid up to March 1 of the first year of a bird's life.
Halaman 37 - Many more instances of this kind could be brought forward. Taken together, the whole evidence shows beyond the shadow of a doubt that the presence of high fecundity in an individual, and that factor which makes high fecundity appear in the progeny, are two very different things, either of which may be present in an individual without the other.
Halaman 47 - Another example of the same thing from line 0310447 may be given by way of further illustration. In this line there was in the Fi generation a family of ten daughters. Of these some were very good and some were poor layers. All were bred. The mean results are shown in the next table. EFFECT OF SELECTION OF GOOD AND POOR WINTER LAYERS IN THE...
Halaman 44 - E248 may be supposed to have originated from the union either of two "high fecundity" gametes or one high and one low fecundity gamete. She then would be either a DD or a DR bird, on the assumption, which the facts seem to support, and which I have more fully discussed elsewhere,** that high fecundity is dominant over low. * Omitting 0495. See text. ** "Inheritance in 'Blood Lines' in Breeding Animals for Performance, with Special Reference to the 'zoo-egg' Hen,
Halaman 48 - ... the great majority of individuals. This, of course, is a direct consequence of the manner of reproduction. The germ plasm of two separate individuals must unite to form a new individual. By prolonging incestuous mating one may in theory come indefinitely close to reproductive purity, but in practice even this is extremely difficult, if not impossible of accomplishment on any large scale or through any long period of time. The fact simply is that a "pure line...
Halaman 162 - Monthly meetings shall be held at such time and place as shall be designated by the executive committee.
Halaman 37 - Note added in reprinting.] and showing the occurrence of high and low fecundity lines. As a typical example of a high fecundity pedigree line in which the high fecundity is genotypic, line D5D39 may be considered. In the presentation of this and other pedigree tables the following conventions are adopted. The band numbers of the birds are in bold-faced type, and following the band number of each female, her winter egg record is given in italic figures enclosed in parenthesis. The band numbers of...
Halaman 31 - Figures i to 5 inclusive of the original publication become figs. 80 to 84 respectively in this reprint. provided only that they conform to purely statistical canons of homogeneity. This assumption of equal hereditary significance for all variations is tacitly made in deducing the law of ancestral inheritance, when individuals are lumped together in a gross correlation table.* The genotype concept, on the other hand, takes as a fundamental postulate, firmly grounded on the basis of breeding experience,...

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