Visar resultat 1 - 5 av 345 avhandlingar innehållade ordet breeding.
Sammanfattning : Around 1750 a German chemist discovered it to be possible to extract sugar crystals from beet juice. Since then, breeding and improved agricultural practices have increased the concentration of sucrose per root from around 4% to around 18%. LÄS MER
Sammanfattning : In extensive grazing systems where several owners’ flocks are allowed to mix, selection strategies will also interact, due to gene flow between flocks. The aim of the thesis was to analyse breeding schemes in terms of genetic gain and rate of inbreeding (?F), given the complexity of ownership and interaction of selection strategies within a mixing reindeer population. LÄS MER
Sammanfattning : Group-living sets the scene for complex social behaviours such as cooperative breeding, and exploring the factors that shape group-living is crucial in understanding these behaviours. This thesis explores the ecology of a population of the facultative cooperative breeding southern anteater-chat (Myrmecocichla formicivora), a group-living bird species endemic to southern Africa. LÄS MER
Sammanfattning : Plant breeding is largely depending on the repeated selection for desirable traits. This process is both time and labour consuming, making the development of commercial plant varieties a slow and costly activity. LÄS MER
Sammanfattning : Ett stort antal utrotningshotade djurarter ingår idag i bevarandeprogram världen över. Små populationer hålls då i skyddade miljöer, exempelvis i djurparker, och i många fall är målet att återintroducera djur till naturen. LÄS MER