FACTORS AFFECTING LITTER SIZE IN THE SCOTCH HALF-BRED EWE
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چکیده
منابع مشابه
Factors Affecting Litter Size in Pigs
Litter size in pigs has been defined in a number of ways, depending on the goals of the specific experiment. Number of total piglets, including mummies and stillborns, number of fully formed piglets, excluding mummies but including stillborns, and the number of piglets born alive have all been used as endpoints of litter size research. The end measures are chosen with the idea that the causes o...
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Lamb's birth weight and litter weight were found to be related to ewe weight. Deviations from generally applicable formulae indicated an interaction between the genotype of the lamb and the maternal environment, as suggested in egg transfer experiments. Land's (1977) hypothesis on the spare conceptus capacity, when comparing large and small breeds within a species, with respect to prolificacy, ...
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Latterly much attention has been attracted, and rightly so, to the number, variety, and potency of the socio-economic factors which strongly incline married couples deliberately to restrain their fertility and thereby to limit the size of-their families. A tendency to overlook a number of purely biological factors which work in the same direction is to be discerned. These latter are for the mos...
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A performance data set from 376 Ripollesa purebred ewes of the experimental flock of the Universitat Autònoma of Barcelona was analyzed using a bivariate Bayesian threshold-linear model. The data set contained 1,598 litter size records and 1,699 days-to-lambing records. The model included the additive genetic effect of each animal and 3 nongenetic sources of variation: ewe age, year of lambing,...
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ژورنال
عنوان ژورنال: Reproduction
سال: 1968
ISSN: 1470-1626,1741-7899
DOI: 10.1530/jrf.0.0170485