A market survey was performed on caviar from Romania and Bulgaria, two of the last range states of critically endangered sturgeons threatened by poaching and illegal trade. Twenty‐seven samples were ...collected between April 2011 and February 2012, including two samples of Bulgarian farm caviar bought in an Austrian fish shop. Mitochondrial sequences of the cytochrome b gene and microsatellites were used for species identification. Ten samples were in agreement with the species code on their CITES labels, but four samples were mislabeled, six samples were counterfeit and four samples were offered as ‘wild origin,’ ignoring the fishing bans in place. At least one sample was upgraded from a lower priced species to a more expensive species. These results demonstrate the weakness of sturgeon protection in these Member States of the European Union and key range states. Therefore, we recommend intensifying conservation and enforcement efforts, including also DNA testing of caviar in containers with apparently correct CITES labels.
The impact of a link adaptation feedback interval on user net throughput for time division multiple access (TDMA)-based single-carrier very high frequency (VHF) narrowband mobile ad-hoc networks ...(MANETs) is investigated. Specifically for the narrowband MANETs optimisation of the signalling overhead is one of the major challenges. Reducing the overhead means that more user data can be transmitted; however, the quality of channel quality feedback information will be lower, resulting in potentially inaccurate link adaptation decisions. The results from Monte Carlo computer simulation show that a global maximum for the throughput with respect to interval exists. The achievable throughput, however, strongly depends on the user mobility pattern.
Summary
The White Park Cattle (WPC) is an indigenous ancient breed from the British Isles which has a long‐standing history in heroic sagas and documents. The WPC has retained many primitive traits, ...especially in their grazing behaviour and preferences. Altogether, the aura of this breed has led to much speculation surrounding its origin. In this study, we sequenced the mitogenomes from 27 WPC and three intronic fragments of genes from the Y chromosome of three bulls. We observed six novel mitogenomic lineages that have not been found in any other cattle breed so far. We found no evidence that the WPC is a descendant of a particular North or West European branch of aurochs. The WPC mitogenomes are grouped in the T3 cluster together with most other domestic breeds. Nevertheless, both molecular markers support the primitive position of the WPC within the taurine breeds.
Summary
Genotype structure of Acipenser ruthenus was investigated using microsatellites and mtDNA sequence analyses of 247 specimens of 13 locations from the rivers Danube, Volga and Kuban. These ...studies were done as an essential prerequisite for the conservation of the uppermost relict sterlet population which is located in the Danube River near the border between Germany and Austria. In contrast to the Volga population, which shows weak signs of a separation in at least three sub‐populations, both microsatellite profiles and mitochondrial sequences indicate a panmictic population of Danube sterlets. Importantly, introgression of non‐native Volga sterlets and a few hybrids with Acipenser baerii were discovered. We observed approximately 23% of non‐native sterlets with complete or at least partly Volga background within the Danube sterlets. Nevertheless, approximately 77% of Danube sterlets were pure native fish. We would like to suggest using these natives for supportive breeding and stocking to avoid any possible outbreeding depressions.
When the American sea sturgeon swam east Ludwig, Arne; Debus, Lutz; Lieckfeldt, Dietmar ...
Nature (London),
10/2002, Letnik:
419, Številka:
6906
Journal Article
Recenzirano
The two species of Atlantic sea sturgeon on either shore of the North Atlantic, Acipenser sturio in Europe and A. oxyrinchus in North America, probably diverged with the closure of the Tethys Sea and ...the onset of the North Atlantic Gyre 15-20 million years ago, and contact between them was then presumably precluded by geographic distance. Here we present genetic, morphological and archaeological evidence indicating that the North American sturgeon colonized the Baltic during the Middle Ages and replaced the native sturgeon there, before recently becoming extinct itself in Europe as a result of human activities. In addition to representing a unique transatlantic colonization event by a fish that swims upriver to spawn, our findings have important implications for projects aimed at restocking Baltic waters with the European sturgeon.
Whereas reliable mtDNA-based methods for species identification of sturgeon caviar are at hand, the development of techniques to separate populations (stocks) or different sources (wild vs farmed) is ...presently at a preliminary state. We tested three methods, Differential Scanning Calorimetry, determination of stable isotopes (δ¹⁵N and δ¹³C), and mRNA analysis (reverse transcription polymerase chain reaction), for their diagnostic power for population and/or source identification of caviar. Farmed caviar (Acipenser baerii) from northern Germany and caviar samples presented by a trading company (Huso huso, Acipenser stellatus, Acipenser gueldenstadtii, Acipenser persicus from Iran and Kazakhstan) were included. Firstly, several DNA-based methods (single strand conformation polymorphism analysis, restriction fragment length polymorphism, sequence analysis) were used for species identification. Sequence analysis of cytb showed the largest diagnostic power. According to population and source identification issue, we conclude that all three methods have considerable potential. Nevertheless, additional methods like fatty acid profiling should be added for a reliable identification of populations and sources.
A continent‐wide survey of sequence variation in mitochondrial (mt) and nuclear (n) DNA of the endangered great bustard (Otis tarda) was conducted to assess the extent of phylogeographic structure in ...a morphologically monotypic bird. DNA sequence variation in a combined 809 bp segment of the mtDNA genome from 66 individuals from the last six breeding regions showed relatively low levels of intraspecific sequence diversity (π = 0.32%) but significant differences in the regional distribution of 11 haplotypes (ΦST = 0.49). Despite their exceptional potential for dispersal, a complete and long‐term historical separation between the populations from the Iberian Peninsula (Spain) and mainland Europe (Hungary, Slovakia, Germany, and Russia) was demonstrated. Divergence between populations based on a 3‐bp insertion–deletion polymorphism within the intron region of the nuclear CHD‐Z gene was geographically concordant with the primary subdivision identified within the mtDNA sequences. Inferred aspects of phylogeography were used to formulate conservation recommendations for this endangered species.
Equid herpes virus 1 (EHV-1) related isolates from a captive blackbuck (strain Ro-1) and Grevy's zebra (strain T965) behaved similarly to EHV-1 and EHV-9 in respect to their host cell range. ...Restriction enzyme analysis and a phylogenetic tree confirmed that Ro-1 and T965 were identical and more closely related to EHV-1 than to EHV-9. Differences from EHV-1 became obvious firstly, by amino acid alignments revealing two unique substitutions in the gB protein of Ro-1 and T965. Secondly, an EHV-1 type-specific monoclonal antibody did not detect its antigen on Ro-1, T965 or EHV-9 infected cells by immunohistochemistry. The results support the view that Ro-1 and T965 isolates represent a distinct, previously unrecognized species of equid herpesviruses.
In one population of
Scardinius dergle, mitochondrial DNA was observed originating from
Squalius tenellus.
Scardinius dergle shared all diagnostic morphological characters and similarities at a ...highly variable nuclear region with the genus
Scardinius. While crosses and backcrosses most likely resulted in the loss of morphologically diagnostic
Squalius-features, maternal inheritance of mtDNA fixed their diagnostic substitutions. Anthropogenic influences resulting from dam building in 1962 are suspected to be the initial force for the hybridization events. However, because hybridization took place despite both lineages being only very distantly related (
p
=
11.2%), we conclude that introgressive hybridization events can be seen as generally possible among leuciscine cyprinids.
The recently described elephant endotheliotropic herpesviruses (EEHV) have been associated with the deaths of numerous captive elephants. A proposed tool for the detection of EEHV infection in ...elephants is the PCR-based screening for EEHV-DNA in whole blood samples. Unfortunately, this detection method has only been successful in post-mortem analyses or in animals already displaying clinical signs of EEHV disease, thus rendering this method unsuitable for identification of carrier elephants. Here, we focus on glycoprotein B (gB) for serologic assay development, since gB is an envelope protein known to induce a neutralising antibody response in other herpesvirus infections. We sequenced the entire gB gene from five Asian elephants with EEHV, representing four different gB variants. Computer-aided methods were used to predict functionally important regions within EEHVgB. An extra-cytoplasmic region of 153 amino acids was predicted to be under positive selection and may potentially contain antigenic determinants that will be useful for future serologic assay development.
PDF
