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Our previously published second generation genetic map for the American mink (Neovison vison) has been used and redesigned in its best for genome-wide studies with maximum of efficiency. A number of 114 selected markers, including 33 newly developed microsatellite markers from the CHORI-231 mink Bacterial Artificial Chromosome (BAC) library, have been genotyped in a two generation population composed of 1200 individuals. The outcome reassigns the position of some markers on the chromosomes and it produces a more reliable map with a convenient distance between markers. A total of 104 markers mapped to 14 linkage groups corresponding to the mink autosomes. Six markers are unlinked and four markers are allocated to the X chromosome by homology but no linkage was detected. The sex-average linkage map spans 1192 centiMorgans (cM) with an average intermarker distance of 11.4 cM and 1648 cM when the ends of the linkage groups and the autosomal unlinked markers are added. Sex-specific genetic linkage maps were also generated. The male sex-specific map had a total length of 1014.6 cM between the linked markers and an average inter-marker interval of 9.7 cM. The female map has a corresponding length of 1378.6 cM and an average inter-marker interval of 13.3 cM. The study is complemented with additional anchorage for most of the chromosomes of the map by BAC in situ hybridization with clones containing microsatellites strategically selected from the various parts of the genome. This map provides an improved tool for genetic mapping and comparative genomics in mink, also useful for the future assembly of the mink genome sequence when this will be taken forward. (C) 2012 Elsevier B.V. All rights reserved.

Phylogeographic relationships were constructed for 72 Old and New World Crataegus species using combinations of four chloroplast and up to five nuclear regions. Maximum parsimony, maximum likelihood, and Bayesian results yield consistent relationships among major lineages. The close associations of the East Asian and western North American species point toward ancient trans-Beringian migrations. Relationships among eastern North American species are poorly resolved and few groups are identified that are congruent with existing classifications. Scant variation and short internal branches among these species suggest rapid divergence associated with polyploidy and hybridization. Incongruence between the chloroplast and nuclear data, and morphology suggest hybrid origins of three species from an extinct European lineage (the male parent) and three different North American female parents. Europe and eastern North America are suggested as the most recent common areas for Crataegus; at least four dispersal events are inferred to explain the present distribution of the genus.

A study was performed to characterize dark brown or black discoloured kidneys ("black kidneys") in Danish slaughter cattle and to investigate the aetiology and pathogenesis. In 133 939 cattle entering four abattoirs, 359 cases of "black kidneys" were recorded. Of these, 57 cases were submitted for macroscopical, microscopical, and ultrastructural examination. A pigment with characteristics similar to those of lipofuscin was found in secondary lysosomes in epithelial cells of the proximal tubules. Pigment accumulation was the cause of discoloration, with a positive correlation between the discoloration of the renal cortex and the degree of pigment accumulation. Cases occurred only in cattle of the Holstein breed or the Red Danish Dairy breed and mainly in animals aged 3 years or older. In these breeds, prevalences of 0.44% and 2.51% were found, respectively. Epidemiological analyses indicated that affected animals aged 4.5 to 6.5 years or 7.5 to 8.5 years were culled more frequently than unaffected cattle. Epidemiological and genealogical analyses strongly indicated a genetic aetiology with simple autosomal recessive inheritance.

The cytogenetic quality of boars used for breeding determines the litter outcome and thus has large economical consequences. Traditionally, quality controls based on the examination of simple karyograms are time consuming and sometimes give uncertain results. As an alternative, the use of high-resolution DNA flow cytometry on DAPI-stained sperm cell nuclei (CV≤1.3%) was investigated as a screening method for the cytogenetic quality of boars. By analyzing a series of 25 animals judged normal by their fertility statistics and a series of seven animals with known reciprocal translocations, a model for identifying sperm cells from cytogenetically aberrant animals was proposed. This model was applied to a series of 50 uncharacterized animals. The model successfully identified a mosaic or chimaeric carrier of an aberrant X chromosome. However, implementation of this technique for screening purposes would necessitate essential improvements in standardization and measurement precision.