Results 251 to 260 of about 6,153 (299)

STUDIES ON INDICES AND CAUSES OF PROLIFICACY IN RATS

Endocrinology, 1947
THE objects of this study were twofold: to determine if indices of prolificacy could be developed; to ascertain the cause of the difference in prolificacy in two inbred strains of rats. Studies with chickens (Hays, 1924), and with turkeys (Asmundson, 1941) have shown an inverse relationship between age at sexual maturity and egg production; the early ...
H H, COLE, R B, CASADY
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Ways of screening in selection for prolificacy

Животноводство России, 2021
Результаты применения при селекции на многоплодие свиноматок различных вариантов отбора, базирующихся на наблюдении за поведением животных, использовании комплексных селекционных индексов, а также анализе полиморфизма в генотипах животных ДНК-маркеров как по отдельности, так и в комплексе, позволили выявить наиболее эффективные варианты.
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Prolificacy and visibility versus reputation in the hard sciences

Scientometrics, 2020
Some authors (including ourselves) have argued that the research quality of an individual or group has to be evaluated by peer review based on the originality, strength, reproducibility, and relevance of their publications. As a result, a reputation is built up by the community.
Maziar Montazerian, Edgar Dutra Zanotto, Hellmut Eckert   +2 more
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TO THE ISSUE OF GENETIC IMPROVEMENT OF PROLIFICACY IN SHEEP

Izvestiâ Timirâzevskoj selʹskohozâjstvennoj akademii, 2023
Most sheep breeds are low-prolific, which, along with other reasons, leads to low profitability of the industry. In intensive systems of industrial sheep breeding, high prolificacy of sheep can increase the efficiency of sheep production. Cross-breeding of low-prolific breeds with highrolific breeds has been the main means of genetic improvement ...
М.I. SELIONOVA, М.М. AYBAZOV А.
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The Prolificacy of Dependent Families

American Journal of Sociology, 1923
The University of Wisconsin investigation, Changes in the Size of American Families, shows that 1,895 filled fertile families of native stock, having a son or a daughter in college, averaged 3.35 children, whereas their parents averaged 5.44. This study of 100 dependent families of native stock shows an average of 6.5 children, nearly twice that of the
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Mass selection for prolificacy in maize

Der Züchter, 1967
Results of 5 generations of selection for improved productivity in corn by selecting for prolificacy, a correlated trait, are reported. The regression for gain in yield per cycle of selection relative to the parental variety, Hays Golden, was 6.28%. This compares favorably with a previously reported gain from mass selection in the same variety using ...
J. H. Lonnquist, C. Petrus Peterson
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Genetic Basis of Prolificacy in Sheep

International Journal of Livestock Research, 2014
The aim of any animal breeder is to get maximum possible profit from the domestic livestock. This can be achieved by improving the genetic potential by appropriate selection methods. The selection aimed at increasing fecundity will ultimately improve the reproduction rate and production efficiency in small ruminants.
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Nutrition and sow prolificacy.

Journal of reproduction and fertility. Supplement, 1986
Prolificacy has been defined as the number of viable piglets produced per year or per breeding lifetime. Prolificacy is influenced by age at first successful mating, ovulation rate and embryo survival at each mating, number of live born, viable pigs and the sow's ability to be successfully remated at regular intervals. It is concluded that under normal
F X, Aherne, R N, Kirkwood
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Identification of quantitative trait loci for prolificacy and growth in mice

Mammalian Genome, 1998
Marker-quantitative trait locus (QTL) linkage was evaluated in F2 intercross and backcross mouse populations derived from stocks differing dramatically in prolificacy and mature weight. A highly prolific outbred Quackenbush-Swiss mouse line, or an inbred line derived from it (16.62 +/- 0.22 and 14.64 +/- 0.27 pups per litter, respectively) were used as
B W, Kirkpatrick, A, Mengelt, N, Schulman, I C, Martin   +3 more
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Repeatability of Prolificacy in Sheep

Journal of Animal Science, 1967
E K, Inskeep, A L, Barr, C J, Cunningham
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