The Cantabrian brown bear Ursus arctos population can be seen as a paradigm in conservation biology due to its endangerment status and genetic uniqueness. Therefore, the need to obtain basic demographic data to inform management actions for conservation is imperative. Despite this, empirical data on the size and trends of the Cantabrian bear population are scarce. Here we present the first estimates of population size (Nc) and effective population size (Ne) of the whole Cantabrian brown bear population. We genotyped 270 non‐invasive samples collected during 2006 throughout the entire range of the population and subsequently identified 130 individuals. Different model estimators of Nc based on capture—markrecapture (CMR) procedures were compared. The average for the best three models (Mh Chao, Mh Darroch and CAPWIRE TIRM) yielded a total estimate of Nc = 223 individuals (CI95% = 183–278) and Ne 50 (CI95% = 36–75) providing an Ne / Nc ratio of 0.22. Estimates for the two subpopulations commonly recognized in the Cantabrian range were Nc = 203 (CI95% = 168–260) and Ne = 47 (CI95% = 36–70) for the western subpopulation and Nc = 19 (CI95% = 12–40) and Ne= 9 (CI95% = 8–12) for the eastern subpopulation. These data suggest that the Cantabrian brown bear population has increased recently, mainly in the western subpopulation, after a long period of decline and isolation which lead to the split of the population at the beginning of the 20th century. Population sizes in the early 1990s were thought to be only 60 individuals for the western subpopulation and 14 individuals in the eastern one. The efforts to improve conservation policies made since then have probably contributed, to some extent, to the population increase during the last couple of decades.
Microsatellite mutations were studied in a set of 175 mutation accumulation lines, all of them independently derived from a completely homozygous population of Drosophila melanogaster and maintained under strong inbreeding during 80 generations. We assayed 28 microsatellites and detected two mutations. One mutation consisted of a single addition of a dinucleotide repeat and the other was a deletion of five trinucleotide repeats. The average mutation rate was 5n1i10 −' , in full agreement with previous estimates from two different sets of mutation accumulation lines.
DNA fingerprinting allows the verification of conventional methods used to implement beef traceability. At any point along the supply chain, the identity of an animal or piece of meat can be checked by comparison of its DNA profile with an initial sample. Practical application of DNA fingerprinting to trace beef requires a choice of DNA markers as well as the optimization of sampling methods. This has been achieved as the result of collaboration between meat technicians and geneticists over a period of 4 years. The discrimination power of nine highly polymorphic microsatellite markers was evaluated. We propose that three markers (with a 0.001 probability that two individual profiles match by chance) are adequate for routine tests. Two key points along the production-commercialization chain where sampling must be systematic were defined: (i) the tagging of the calf (identity control) and (ii) after slaughter (slaughter control), before the animal loses its external appearance. The identity control was blood collected on a filter paper adapted to the ear tag; the slaughter control was the tagged ear itself. These constituted the control samples, which were archived with a code matching the individual tag number. Test samples were obtained on a random basis from live animals, carcasses, and pieces of meat at cutting halls and at the retail outlet and in cases when the verification of identity was needed. The DNA profiles of the test samples and the controls were then obtained and compared, to verify either an individual identity or the origin of a piece of meat from the stated animal.
A set of 14 microsatellite loci were used for amplification of faecal DNA from capercaillie (Tetrao urogallus). New internal primers were designed for each locus and were employed to perform a seminested PCR approach combined with a multiplex preamplification method. The aim of this process was to increase the quality of the multilocus genotypes and to reduce the amount of sample required. Values of allelic dropout and false alleles found after three repetitions were 8.1 and 1.4% respectively, and 52.63% of the samples amplified for a minimum of 12 loci. Additionally, capercaillie specific sex primers have been designed. These primers give short products suitable for degraded faecal sample amplification. New primers resulted in 87.5% of samples being successfully sexed, a value seven times higher than using the original P2/P8 CHD sexing method.
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