THE ESTIMATION OF GENETIC DISTANCE BETWEEN GERMAN CATTLE BREEDS

Za budući izbor uzgoja potrebno je očuvanje genetske raznolikosti u životinja. U filogenetskim proučavanjima mikrosateliti su dokazani kao snažno sredstvo. (Bowcock et al. 1994.). Procjena genetskih udaljenosti što se temelji na učestalosti alela mikrosatelitskih markera pomoći će u procjeni veličine razlika između usko povezanih pasmina stoke. Pasmina Shorthom i Angler mogu se identificirati kao sporedne pasmine, pa je stoga razvoj programa očuvanja vrlo koristan. Prilagođenje pasmine Orginal Black Pied još nije jasno. Odredit će se dodatni markeri kako bi se povećala točnost procjene. Niti vrijednosti udaljenosti između Holsteina i mliječnog Red Pied niti slični uzgojni ciljevi čini se da nisu razuman razlog da se ove pasmine drže odijeljeno. Ovaj će rad biti od pomoći u odlučivanju o očuvanju pasmina u posebnim programima očuvanja konzervacijom in vivo i in vitro

Genetic diversity among some cattle breeds in the Alpine area

Seven autochthonous Italian cattle breeds bred in the alpine area (Aosta Black Pied, Aosta Red Pied, Aosta Chestnut, Oropa Red Pied, Grey Alpine, Rendena and Burlina) were investigated in order to characterise their genetic structure and to study their phylogenetic origin. Two cattle breeds from Germany (Original German Brown and Holstein) and four from Switzerland (Simmental, Herens, Evolene and Brown Swiss) were included in the study in order to determine the genetic diversity existing among Italian local breeds, similar breeds bred on the other side of the Alps and in the well known Holstein. Seventeen microsatellites, of the internationally accepted panel for the study of cattle biodiversity, were used for the analysis. Microsatellites were highly polymorphic with a mean number of 5,5 alleles (ranging from 2 to 12 per locus). For each locus, allelic frequencies, heterozygosity (H) and the Polymorphism Information Content (PIC) were computed. The genetic equilibrium according to Hardy\ub1Weinberg was calculated for each population and for each locus. Allele frequencies were used to estimate genetic distances and to draw a phylogenetic tree. The two closest breeds were Aosta Red Pied and Aosta Black Pied, while the two genetically most different were Holstein and Aosta Chestnut. Aosta valley breeds, Evolene and Herens constituted a tight cluster in the phylogenetic consensus tree. Principal component analysis showed a similar pattern for all the alpine breeds, while Holstein and Original German Brown were far away. The genetic differences among breeds were in accordance with their geographical and historical origin

Biodiversity of chickens based on DNA pools: first results of the EC funded project AVIANDIV

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Assessment of biodiversity in a wide range of chicken breeds by genotyping DNA pools for microsatellite loci

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CaDbase - a cattle diversity database

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Marker-assisted conservation of European cattle breeds: an evaluation

Two methods have been developed for the assessment of conservation priorities on the basis of molecular markers. According to the Weitzman approach, contributions to genetic diversity are derived from genetic distances between populations. Alternatively, diversity within and across populations is optimized by minimizing marker-estimated kinships. We have applied, for the first time, both methods to a comprehensive data set of 69 European cattle breeds, including all cosmopolitan breeds and several local breeds, for which genotypes of 30 microsatellite markers in 25-50 animals per breed have been obtained. Both methods were used to calculate the gain in diversity if a breed was added to a set of nine non-endangered breeds. Weitzman-derived diversities were confounded by genetic drift in isolated populations, which dominates the genetic distances but does not necessarily increase the conservation value of a breed. Marker-estimated kinships across populations were less disturbed by genetic drift than the Weitzman diversities and assigned high conservation values to Mediterranean breeds, which indeed have genetic histories that differ from the non-endangered breeds. Prospects and limitations of marker-assisted decisions on conservation priorities are discussed