Search for dissertations about: "egg-production"
Showing result 1 - 5 of 27 swedish dissertations containing the word egg-production.
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1. Genomics of heterosis and egg production in White Leghorns
Abstract : Crossbreeding is practiced extensively in commercial breeding programs of many plant and animal species, in order to exploit heterosis, breed complementarity, and to protect pure line genetic material. The success of commercial crossbreeding schemes depends on identifying and using the right combination of breeds, lines or varieties that produce the desired crossbred offspring. READ MORE
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2. Mapping Genes Affecting Phenotypic Traits in Chicken
Abstract : The purpose of gene mapping is to understand the underlying genetics of simple and complex traits like plumage colour and growth. This thesis is based on a cross between the wild ancestor of the modern chicken, the red junglefowl, and a White Leghorn line selected for high egg mass. READ MORE
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3. Non-indigenous zooplankton : the role of predatory cladocerans and of copepods in trophic dynamics
Abstract : Human-mediated introductions of non-indigenous species now threaten to homogenize the biota of the Globe, causing huge economic and ecological damage. This thesis studies the ecological role of 3 invasive planktonic crustaceans, the omnivorous copepod Acartia tonsa (western Atlantic and Indo-Pacific) and the predatory cladocerans, Cercopagis pengoi (Ponto-Caspian) and Bythotrephes longimanus (Eurasian). READ MORE
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4. Domestication effects on foraging behaviour : consequences for adaptability in chickens
Abstract : The main aim of this thesis was to study domestication effects on foraging behaviour in chickens and to investigate whether and how domestication and selection for high production have influenced adaptability in chickens. Two domestic strains of chickens (egg layers and meat type chickens) and their wild ancestor, the red jungle fowl (RJF) were compared in different test situations with respect to foraging behaviour and adaptability. READ MORE
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5. Effects of domestication related genes on behaviour, physiology and gene expression in chickens
Abstract : Domestication, the process when animals adapt to captivity, tends to modify a whole array of traits towards what has been termed “the domesticated phenotype”, where the domesticated animal differs from its wild ancestor in morphology, physiology, development and behaviour. Physiological traits and behaviours are controlled by genes. READ MORE