Swedish University of Agricultural Sciences

About: Swedish University of Agricultural Sciences is a education organization based out in Uppsala, Sweden. It is known for research contribution in the topics: Population & Soil water. The organization has 13510 authors who have published 35241 publications receiving 1414458 citations. The organization is also known as: Sveriges Lantbruksuniversitet & SLU.

Miscellaneous standard methods for Apis mellifera research

Abstract: SummaryA variety of methods are used in honey bee research and differ depending on the level at which the research is conducted. On an individual level, the handling of individual honey bees, including the queen, larvae and pupae are required. There are different methods for the immobilising, killing and storing as well as determining individual weight of bees. The precise timing of developmental stages is also an important aspect of sampling individuals for experiments. In order to investigate and manipulate functional processes in honey bees, e.g. memory formation and retrieval and gene expression, microinjection is often used. A method that is used by both researchers and beekeepers is the marking of queens that serves not only to help to locate her during her life, but also enables the dating of queens. Creating multiple queen colonies allows the beekeeper to maintain spare queens, increase brood production or ask questions related to reproduction. On colony level, very useful techniques are the measu...

A genetic variation map for chicken with 2.8 million single-nucleotide polymorphisms

Abstract: We describe a genetic variation map for the chicken genome containing 2.8 million single-nucleotide polymorphisms (SNPs). This map is based on a comparison of the sequences of three domestic chicken breeds (a broiler, a layer and a Chinese silkie) with that of their wild ancestor, red jungle fowl. Subsequent experiments indicate that at least 90% of the variant sites are true SNPs, and at least 70% are common SNPs that segregate in many domestic breeds. Mean nucleotide diversity is about five SNPs per kilobase for almost every possible comparison between red jungle fowl and domestic lines, between two different domestic lines, and within domestic lines--in contrast to the notion that domestic animals are highly inbred relative to their wild ancestors. In fact, most of the SNPs originated before domestication, and there is little evidence of selective sweeps for adaptive alleles on length scales greater than 100 kilobases.

Nitrogen stress in birch seedlings. II. N, K, P, Ca, and Mg nutrition

Abstract: In a series of experiments with nitrogen stress, optimum and supra-optimum nitrogen supply, N, K, P, Ca, and Mg have been analysed in leaves, stems and roots of birch seedlings (Betula oerrucosa Ehrh.). Growth rate was strongly and linearly correlated with the nitrogen status of the seedlings within the whole sub-optimum range. Seedling weight was equally strongly correlated with nitrogen status, although exponentially. Various expressions for growth rate and nitrogen status give similar results. Nitrogen efficiency (dry matter produced per unit nitrogen) decreased with increasing nitrogen status, but nitrogen productivity (dry matter produced per unit nitrogen and time) increased up to optimum. The maintenance of a stable nitrogen status in the seedlings and a stable growth rate requires an accurate and closely controlled technique of nitrogen addition. Because of the exponential relation between seedling weight and sub-optimum nitrogen status and a rapid decrease in the supra-optimum range, a strict control of the optimum status is necessary to maintain maximum growth.

The value relevance of environmental performance

Abstract: This paper provides insight into how environmental information is reflected in the market value of listed Swedish companies. Using the residual income valuation model, we express market value of eq ...

Genetic dissection of phenotypic diversity in farm animals

Abstract: Farm animal populations harbour rich collections of mutations with phenotypic effects that have been purposefully enriched by breeding. Most of these mutations do not have pathological phenotypic consequences, in contrast to the collections of deleterious mutations in model organisms or those causing inherited disorders in humans. Farm animals are of particular interest for identifying genes that control growth, energy metabolism, development, appetite, reproduction and behaviour, as well as other traits that have been manipulated by breeding. Genome research in farm animals will add to our basic understanding of the genetic control of these traits and the results will be applied in breeding programmes to reduce the incidence of disease and to improve product quality and production efficiency.