Genetic monitoring of horses in the Czech Republic: A large-scale study with a focus on the Czech autochthonous breeds.

We propose the first comprehensive in-depth study monitoring horses in the Czech Republic. We scanned 9,289 animals from 44 populations for 17 equine STRs. Other equids analysed involved Equus przewalskii and Equus asinus. The total of 228 different alleles were detected, with the mean number of 13.4 per locus. The highest allelic richness (AR) was found in the Welsh Part Bred (6.01), followed by the Camargue (5.93) and Czech Sport Pony (5.91), whereas the Friesian exhibited the lowest AR (3.06). Interpopulation differences explained approximately nine per cent of the total genetic diversity. Reynold's genetic distance ranged from 0.003 between the Czech Warmblood and the Slovak Warmblood to 0.404 between the Friesian and donkeys. Close genetic proximity between the Silesian Noriker and Noriker was revealed. The Moravian Warmblood was better differentiated and more distant from the Czech Warmblood than the Kinsky Horse and retained the original genes of the old Austro-Hungarian tribes. A high gene flow level and a lack of genetic structure were found in the seven studied populations. Despite the historical bottlenecks and previous inbreeding, the Czech-Moravian Belgian Horse, Hucul, Old Kladruber Horse and Silesian Noriker did not suffer a serious loss of genetic diversity due to genetic drift/low effective population size. A NeighborNet dendrogram revealed breeds not classified in their groups according to the nomenclature (the Friesian, Hafling and Merens).

Epidemiology of intramammary infections with Staphylococcus aureus and mastitis streptococci in a dairy cattle herd with a history of recurrent clinical mastitis.

The aim of the present work was to examine a dairy herd with an anamnesis of recurrent clinical mastitis and decreased milk production. A total of 239 individual cow milk samples originating from asymptomatic cows were collected at four-month intervals and examined mainly for the presence of Staphylococcus aureus and mastitis streptococci using standard cultivation methods. In total, 29.7% and 9.2% samples were positive for S. aureus and mastitis streptococci, respectively. Unlike for mastitis streptococci, the prevalence of animals positive for S. aureus had an increasing trend (p<0.05; Chi-squared test for trend) with rising parity. Despite in vitro susceptibility of S. aureus to potentiated penicillins and cephalosporins, the persistence of S. aureus was observed in cows undergoing intramammary treatment with amoxicillin/clavulanic acid (a potentiated penicillin antibiotic). All isolates of S. aureus were biofilm-positive and had the same macrorestriction pattern. Furthermore, no dependence was observed between the occurrence of S. aureus in milk and previous cases of clinical mastitis, reproductive and periparturient disorders and administration of antibiotics. In contrast to S. aureus, the occurrence of mastitis streptococci in milk was linked with previous cases of clinical mastitis and intramammary administration of antibiotics.

Association between CSN3 and BCO2 gene polymorphisms and milk performance traits in the Czech Fleckvieh cattle breed.

Daily milk, fat and protein yield and amount of somatic cells in cow milk are very important factors that influence milk performance traits. An association between polymorphisms in the kappa casein (CSN3) gene and milk production, composition and technical properties has been previously reported; however, this type of information is not available for the bovine ß-carotene oxygenase 2 (BCO2) gene--the BCO2 gene has relationship with milk color and meat fat color, which is dependent on content of ß-carotene. We analyzed these two genes and their relationship with milk performance traits (daily milk, fat and protein yield, somatic cell count, SCC) in one cattle population, Czech Fleckvieh (N = 152). All animals were milked twice a day and kept in the same environmental conditions. The Fleckvieh is a typical Czech cattle breed farming for milk and meat production. It is the most common breed in the Czech Republic. DNA was isolated from milk or from hairs. Genes were analyzed using PCR-RFLP, frequencies of alleles and genotypes were calculated and association analysis was performed using a GLM Procedure in SAS. Statistical analysis established that the CSN3 gene has no statistically significant influence on daily milk, fat and protein yield and SCC. Compared to other references this result can be explained by, e.g., small group of animals and different cattle breed. The BCO2 gene (genotypes AA and AG) shows a statistically significant relationship (P = 0.05) with daily milk, protein yield and SCC.

Micro-RNAs miR125b and miR137 are frequently upregulated in response to capecitabine chemoradiotherapy of rectal cancer.

There is increasing evidence that some microRNAs change their levels in reaction to xenobiotic challenge. The aim of this study was to test the possible involvement of micro-RNAs in response to standard anticancer treatment. Tumor biopsies from 35 patients with rectal cancer before therapy and parallel tumor biopsies from 31 patients two weeks after starting preoperative capecitabine chemoradiotherapy were taken. The expression levels of single miRNA species were measured using TaqMan Micro-RNA assays after reverse transcription from isolated total RNAs. Many micro-RNAs (miR10a, miR21, miR145, miR212, miR339, miR361) responded to chemoradiotherapy in individual tumor samples, but there was profound intertumoral variability. However, other two micro-RNAs miR125b, miR137 showed a significant increase in median expression levels after starting therapy in most samples. Moreover, our results for the first time show that higher induced levels of miR125b and miR137 are associated with worse response to the therapy.

Frequencies of alleles and genotypes of the PRNP gene in Polish Red, Czech Pied and Czech Black-and-White cattle.

Frequencies of alleles and genotypes of the PRNP gene in 65 Polish Red cows kept under a conservation programme and 52 randomly chosen cows of two Czech breeds: Czech Pied (42) and Black-and-White (10) were studied. All cows were at the age of 4 years or older. It was found that the frequency of allele 5 (5 copies of the octapeptide repeat) ranged from 0.11 (Polish Red) to 0.00 (Czech Black-and-White) whereas the frequency of allele 6 (6 copies of the octapeptide repeat) ranged from 1.00 (Czech Black and White) to 0.89 (Polish Red). The highest frequency was found for the homozygous genotype 6/6 (1.00 in Czech Black-and-White) and the lowest frequency was detected for the heterozygous genotype 6/5 (0.143). In the studied cows the genotype 5/5 was not found. The higher frequency of allele 5 in the native breeds and its lower frequency or lack of this allele in the populations intensively selected for high milk production may suggest that alleles of the PRNP gene may be associated with milk production.

Association od the DdeI growth hormone gene polymorphism with some performance traits in Polish Large White and Czech Large White x Polish Large White pigs.

The genotypes of growth hormone gene polymorphisms (GH-DdeI, GH-MspI, GH-HaeII, GH-ApaI, GH-CfoI) were determined in 78 pigs [Czech Large White sires (CLWsire line) x Polish Large White (PLW) sows, Polish Large White sires x Polish Large White sows], by the PCR-RFLP method. Preliminary studies found only GH DdeI polymorphism to be associated with performance traits. The associations of this polymorphism with growth and carcass traits were investigated. The linear model included the effects of candidate genes, genetic groups, sex and linear covariables of age at slaughter and body weight at weaning. The DdeI polymorphism of the GH gene showed associations with carcass length (P

Genetics of anti-EHV antibody responses in a horse population.

Individual variation in immune responses to herpesviruses was observed in various species. Here, associations between polymorphic molecular markers and life-long anti-EHV-1/4 antibody immune responses were analyzed in a model EHV-infected population of the Old Kladruber horses. Two-dimensional analysis including overall mean titers and titer dynamics expressed by differences between spring and autumn titers allowed identification of low-responders. 50 randomly selected microsatellites and nine single nucleotide polymorphisms in nine immunity-related candidate genes were genotyped. Due to differences (p<0.001) in antibody titers between two color varieties of Old Kladruber horses, separate association studies were performed in the two sub-populations by using the Fisher's exact test. In black horses, the interleukin 4 receptor and MxA protein coding genes, and the microsatellite TKY325 were associated with the responder status. In the grey population, the microsatellite TKY343 showed significant association with anti-EHV antibody responsiveness after Bonferroni corrections.