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Basing on the polymorphism at 26 DNA microsatellite loci an estimation was made of the mean number of genes migrating in one generation (Nem) between populations of nine cattle breeds maintained in Germany, Switzerland and Poland: Angler, German Simmental, Brown Swiss, Swiss Simmental, Holstein, Eringer, Polish Red (PR – included in the National Rare Livestock Breeds Preservation Programme), Polish Black-and-White (PBW) and Polish Red-and-White (PRW). The Nem value for the whole population amounted to 2.048. When the breeds were grouped according to the country of origin the greatest flow of genes was observed within the Polish (2.023), while the lowest within the German population (1.214). The Nem values estimated when comparing each breed with each show that the greatest exchange of genetic material took place between breeds from the same geographic regions. On the phylogenetic N-J tree, constructed on the basis of genetic distance DA, the PR were classified together with PBW and PRW cattle. However, when evaluating the relations between breeds on the basis of values estimated for the DSW genetic distance, the PR cattle were classified together with the Angler breed. Bootstrap values were higher when the tree was constructed on the basis of the DA and not the DSW distance, what indicates a higher reliability of the genealogical structure determined on the basis of the former. In turn, the DSW distance gave a more precise information about the common background of the German and Swiss Simmentals, as well as about the share of the Angler breed used in the past for upgrading the PR.
On the basis of DNA microsatellite polymorphism at 26 loci tested within the European Concerted Action AIRE 2066 for the Analysis of Genetic Diversity to Preserve Future Breeding Options, a determination was made of the genetic structure of 147 Polish Red (PR) cattle, included in the National Rare Livestock Breeds Preservation Programme (NRLBPP). The examined PR cattle population was characterized by a high genetic variation (a total of 193 alleles identified, Ho = 0.695, He = 0.703,mean number of alleles per locus = 7.4). An analysis of the genetic distance (Dps), including information on the presence (or absence) in the genome of alleles specific for the breed, confirmed that 80% of PR animals included in the NRLBPP comprised a separate genetic group, differing from populations of other European cattle breeds. The results show the uniqueness of the gene pool of PR cattle included in the NRLBPP. Despite the crossing with other breeds widely applied in the past, the present PR material does, to a considerable degree, remain genetically distinct. Thus, it is anticipated that basing on the existing preserved population the reconstruction of a pure, or almost pure PR cattle can be achieved.
The intrabreed and interbreed genetic diversity of Lithuanian cattle breeds - two native, namely Lithuanian Light Grey and Lithuanian White-Backed and two modern, namely Lithuanian Red and Lithuanian Black and White was investigated by determination of genetic markers: 4 milk protein systems, Alphass1-casein, Kappa-casein, Beta-casein and Beta-lactoglobulin, which are comprised of 12 different milk protein types. According to results, the B type of Alphasl-casein was found as predominant in all four studied breeds. The most common A and B types of Kappa-casein were found at high frequency in all investigated cattle breeds. All investigated Lithuanian dairy cattle breeds had high frequency of Beta-lactoglobulin whey protein B types, with the highest frequency in Lithuanian Red breed, and the lowest in Lithuanian Light Grey. After investigation the diversity of alleles and genotypes of milk proteins in Lithuanian dairy cattle breeds was determined that, Lithuanian Red breed was distinguished private C allele and BC genotype of Beta-lactoglobulin and CC genotype of Alphasl-casein. The interbreed genetic diversity was estimated by a principal component analysis (PCA). The first principal component (PC) explains 63.39% and the second principal component (PC) explains 33.67% of the genetics diversity between the breeds. Principal component analysis, suggests the hypothesis that native Lithuanian White Backed and Lithuanian Light Grey breeds still have traits tracing to old native populations.
The aim of the study was to estimate the content of functional components of milk in some major cattle breeds. The study was performed in two parts. The first was conducted on Black-and-White (BW) and Polish Red (PR) cows. All animals were kept as one herd at Popielno, and maintained according to the traditional extensive feeding system. Bulk milk samples were used, representing the milk of 349 Simmental cows (SM) cows, maintained and fed in similar conditions to BW and PR animals. The second part included Black-and-White cows upgraded with HF (BW HF) and Simmental cows (SM). Animals of BWHF and SM breed originated from different herds. However, they were maintained and fed according to a similar system, without access to pasture. Milk was examined for antioxidants, CLA and other functional fatty acids as well as FFA and MDA content indicative of milk fat quality. The milk of SM cows maintained according to the traditional system significantly (p≤0.01) exceeded BW and PR for A and E vitamins, as well as C 4:0, C18:2, C20:4, C20:5, and C22:5, while was lower (p≤0.01) than of BW in the case of fat, MDA, FFA and C vitamin (p≤0.01) content. There was a highly significant interaction of breed and season. During the grazing season milk of BW cows contained significantly more (p≤0.01) fat, C vitamin, C18:1 trans 11 and CLA than that of SM. In the case of animals fed TMR diet, milk of SM exceeded significantly (p≤0.01) that of BW HF cows for fat, protein, CLA, C20:4 and C20:5 content, while MDA, FFA, cholesterol and C18:2 content of milk were higher in BW HF animals. Individual variation of CLA content differed among breeds and was the greatest (over 3 fold) in milk fat of BW cows.
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Transcriptomic index of skeletal muscle of beef breeds bulls

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In the present study cDNA microarray (18263 probes) were used for analysis of bovine skeletal muscle (m.semitendinosus) transcriptome in 12-month-old bulls of four cattle breeds: Holstein-Friesian (HF), Limousine (LIM), Hereford (HER) and Polish Red (PR), aiming to identify the genes, which expression is common for beef breed bulls. The number of transcripts significantly different from HF bulls muscle amounted to 393, 462 and 638 for LIM, HER and PR, respectively. As a result of this study the transcriptomic index was proposed, being the set of 48 genes expressed similarly in beef breed bulls in comparison to HF bulls. Classification of genes according to molecular function of their protein products has shown the highest number of genes encoding proteins involved in nucleic acid binding (10), regulatory proteins (6), kinases (4) and signaling molecules (3). Classification according to biological processes revealed the highest number of genes involved in protein metabolism i modification (14), signal transduction (5), cell cycle (4), intracellular protein traffic (4), nucleoside, nucleotide and nucleic acid metabolism (4), apoptosis (3), cell structure and motility (3), and cellular transport (3). Since the role of the most genes included to the transcriptomic index has not been described yet in bovine skeletal muscle, obtained results may be very useful in revealing new candidate genes to search a new criteria of animal selection in beef production.
The aim of the study was to infer (co)variance components for daily milk yield, fat and protein contents, and somatic cell score (SCS) in Burlina cattle (a local breed in northeast Italy). Data consisted of 13 576 monthly test-day records of 666 cows (parities 1 to 8) collected in 10 herds between 1999 and 2009. Repeatability animal models were implemented using Bayesian methods. Flat priors were assumed for systematic effects of herd test date, days in milk, and parity, as well as for permanent environmental, genetic, and residual effects. On average, Burlina cows produced 17.0 kg of milk per day, with 3.66 and 3.33% of fat and protein, respectively, and 358 000 cells per mL of milk. Marginal posterior medians (highest posterior density of 95%) of heritability were 0.18 (0.09-0.28), 0.28 (0.21-0.36), 0.35 (0.25-0.49), and 0.05 (0.01-0.11) for milk yield, fat content, protein content, and SCS, respectively. Marginal posterior medians of genetic correlations between the traits were low and a 95% Bayesian confidence region included zero, with the exception of the genetic correlation between fat and protein contents. Despite the low number of animals in the population, results suggest that genetic variance for production and quality traits exists in Burlina cattle.
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