Polish Strains Research Articles

The genetic analysis of new Polish strains of European brown hare syndrome virus.

In this paper we describe recently occurring outbreaks of European brown hare syndrome (EBHS) in a captive hare population. The aim of our study was to evaluate the phylogenetic position of detected Polish strains compared to other European strains of EBHSV. Investigations were undertaken in hares from different provinces of Poland. Liver or spleen samples were tested for viral RNA using the RT-nested PCR method and the products were subsequently sequenced. The genetic analysis was based on the fragment of gene encoding viral capsid protein; it revealed a high homology and close relationship between Polish and European EBHSV strains isolated between 2001 and 2011.

Molecular epidemiology of rabies virus in Poland

The paper describes a phylogenetic study of 58 Polish isolates of rabies virus collected between 1992 and 2010. Sequences of the nucleoprotein (N) and glycoprotein (G) genes approximately 600 bp long were compared with reference sequences (GenBank) of European rabies viruses from neighbouring countries. The study confirmed a very high level of homology (94.4–100 %) of the Polish rabies virus strains irrespective of the date of isolation. Two variants of rabies virus: NEE (Northeastern Europe variant) and CE (Central Europe variant), depending on the geographical place of isolation, were circulating in Poland from 1992 to 2010. The Polish rabies virus isolates showed high similarity to European RABV strains, especially those collected in Ukraine and Romania. They were clearly different from vaccine strains SAD B19 and SAD Bern, which have been used for oral vaccination of foxes against rabies in Poland since 1993.

Phylogenetic analysis of Columbid herpesvirus-1 in rock pigeons, birds of prey and non-raptorial birds in Poland

BackgroundThe identity of herpesviruses isolated in Europe from domestic pigeons (Columbid herpesvirus-1 - CoHV-1) as well as falcons and owls remains unknown. All these herpesviruses are antigenically and genetically related. The falcons and owls are thought to have become infected during the ingestion of pigeon meat thus suggesting the virus’s capacity to infect a wide range of hosts. The aim of the conducted study was to detect the occurrence of CoHV-1 and estimating the similarities and differences in the DNA-dependent DNA polymerase gene of herpesviruses isolated from domestic pigeons, birds of prey and non-raptorial free-ranging birds in Poland.ResultsThe study has shown the presence of CoHV-1 in 20.4% (18/88) in the examined birds. In case of one CoHV-1, infected Peregrine Falcon (Falco peregrinus), neurological signs were observed. Nucleotide sequencing of the DNA-dependent DNA polymerase gene, showed a high similarity among Polish strains (100%), independently from the species of the affected birds. Only one compared CoHV-1 strain - KP 21/23 originating from Germany showed a slightly lower similarity at a level of 99.1%. Further analysis has shown the identity of DNA-dependent DNA polymerase of CoHV-1 strains and other herpesviruses present in poultry as well as other birds ranged from 35.4 to 44.9%. Interestingly CoHV-1 infection was also confirmed for the first time in four non-raptorial birds.ConclusionsThe current study has shown a high similarity of CoHV-1 strains and the possible transmission of herpesviruses between domestic rock pigeons and free-ranging birds including raptors and non-raptorial birds. Further studies focused on cloning and the analysis of the whole CoHV-1 genome which is needed to explain the role of the observed similarities and differences between field strains of columbid herpesviruses.

Viral infections in goose flocks in Poland

The aim of this study was to determine the infectious agents isolated from infection - suspected geese sent for the diagnostic examination to National Veterinary Research Institute. The birds were sent from goose flocks localized in different parts of Poland. Totally, 1,013 birds from 122 flocks were examined. The presence of goose parvovirus (GPV), goose haemorrhagic polyomavirus (GHPV), and goose circovirus (GoCV) was detected by triplex PCR. The presence of GPV DNA was shown in 36 flocks. The disease was most frequently diagnosed in goslings aging 3.5 weeks (ten flocks), and 2.5 weeks (six flocks). The analysis of the nucleotide sequence of VP1 encoding region has shown close similarity of Polish GPV strains within the group which ranged from 92% to 100%. Moreover, the similarity level of these strains with GPV isolated in Europe was from 91.3% to 100%. The occurrence of GoCV DNA was shown in 25 goose flocks. The presence of GoCV DNA was found among geese aged from 2 to 6 weeks, but predominantly in those aging 3.5 (three flocks) and 5 weeks (five flocks). The sequence analysis of PCR products from the sequenced region of ORFC1 capsid protein of GoCV has shown that Polish isolates share from 85% to 91% similarity with the sequences of GoCV strains isolated in other countries. The presence of DNA of GHPV was found in 3-week-old geese. During the last 2 years the presence of GHPV was confirmed in three flocks of goslings at the age from 3 to 3.5 weeks. During the last 12 years the occurrence of co-infection with GPV and GoCV was detected in six flocks aging from 5 to 6 weeks.

Identification of Polish RHDVa subtype strains based on the analysis of a highly variable part of VP60 gene

In order to determine the genetic variability of Polish RHD virus strains and to confirm the presence of genetic variant (RHDVa) subtype the partial nucleotide sequences of capsid protein gene, including two highly variable regions C and E, were examined. Phylogenetic analyses of 15 viral strains obtained over 18 years revealed the presence of three genetic groups. The oldest RHDV strains exhibit very close amino acid sequence similarity (98-99%) to the German FRG89 reference strain and most of European strains of the same period, as well as Chinese isolate from 1984. The HA-negative strains and isolates with variable reactivity in the HA test belong to the second subgroup and exhibit an intermediate level of variability (about 3%) in the analysed VP60 gene fragment. The most genetically variable strains (6-7%) clustered to RHDVa subtype. The analysis of nucleotides and amino acid sequences demonstrated three pairs of well conserved RHDV strains, isolated over 3, 6 and 10-year period.

Analysis of the culture-derived soluble Babesia canis canis antigens derived from the Polish strains of the parasites

OBJECTIVE, MATERIAL AND METHODS: The aim of this study was to analyse the protein fractions of the soluble parasitic antigen (SPA) from in vitro cultures of the native Polish strains of Babesia canis canis and to determine their immunogenicity through Western blotting using the sera of dogs vaccinated with this antigen. Polyacrylamide gel electrophoresis revealed 21 protein fractions with molecular weights from 12 to 205 kDa. The most intense reaction in Western blotting was observed between the serum antibodies of the SPA-vaccinated dogs and the fraction with the molecular weight of 52 kDa. Detailed studies on the composition of SPA of Babesia canis canis and reactivity of its individual protein fractions can be a starting point for the development of subunit vaccines against babesiosis. Using a preparation with only some electrophoretic fractions of SPA in the production of vaccines would allow to avoid putting an unnecessary protein burden in the vaccine which could cause side effects.

Genetic and antigenic characterization of small ruminant lentiviruses circulating in Poland

Small ruminant lentivirus (SRLV) infections are widespread in Poland, but the genetic features of sheep viruses are still lacking and limited to partial gag sequences for goat viruses. In this study, segments from the gag and env genes of Polish SRLV strains screened by heteroduplex mobility assay were subjected to genetic analyses. Subtype A1 was found in both sheep and goats, while subtypes B1 and B2 were found in goats and sheep, respectively. In addition, two novel subtypes (named A12 and A13) were found in sheep. Their close phylogenetic relatedness with SRLV strains previously isolated from Polish goats indicated that these new subtypes are predominant and circulate in both species. The antigenic relationships of subtypes A12 and A13 with other SRLV subtypes were tested in an ELISA assay based on recombinant antigens carrying the immunodominant domains of structural proteins (MA, CA and SU). Antigenic cross-reactivity in the Gag epitopes was evident among genotype A subtypes and, to a lower extent, between genotypes A and B. In contrast, a subtype-specific immunoresponse was detected in the SU epitopes. These results emphasize the broad genetic and antigenic diversity of SRLV strains circulating in Europe and confirmed the need to consider all viral genotypes to choose the antigens in serological tests in order to avoid misdiagnosis in control and eradication programs.

Effect of Housing System on Egg Quality in Laying Hens

Effect of Housing System on Egg Quality in Laying HensThe aim of the study was to evaluate the quality of eggs from hybrids of laying hens of selected Polish breeding strains depending on their housing system. Analysis was made of eggs from KA-62, KA-42, KA-68 and KA-48 hybrids housed in three systems: cage, litter and free range. One hundred eggs, randomly chosen from each experimental group between 34 and 36 weeks of age, were evaluated for a set of physical characteristics such as weight of egg and egg fraction, percentage of main egg fractions, egg shape index, air cell height, albumen height and pH, Haugh units, yolk colour and pH, as well as shell colour, thickness, density and deformation. Caged birds produced the heaviest eggs (61.06 g) with the lowest shape index (77.86%), lightest shell (39.86) and highest percentage of albumen (57.04%) and yolk (29.89%) in the egg. The most favourable quality traits of albumen from the analysed eggs, i.e. greatest height (5.00 mm) and Haugh units (69.70) were characteristic of egg albumen from hens raised on litter. Shell quality analysis showed that the eggs of free-range birds were characterized by the highest weight of shell (5.76 g), which had the greatest thickness (360.14 μm) and density (81.01 mg/cm2). Detailed analysis of the physical characteristics of eggs from the hybrids of laying hens revealed significant (P≤0.05) differences depending on the housing system. The eggs of caged layers showed many characteristics desired by processors. Meanwhile, the eggs of hens kept on litter were characterized by dietetic properties that could meet specific needs of the consumers.

Serotyping of Proteus mirabilis clinical strains based on lipopolysaccharide O-polysaccharide and core oligosaccharide structures

The aim of this work was to serotype Proteus mirabilis urinary tract infection (UTI) strains based on chemically defined O-antigens with the use of two clinical collections from Sweden and Poland consisting of 99 and 24 UTI strains, respectively. A simple two-step serotyping scheme was proposed using enzyme immunoassay with heat-stable surface antigens of Proteus cells and immunoblotting with isolated lipopolysaccharides (LPSs). Using polyclonal anti-P. mirabilis rabbit antisera, 50 Swedish and 8 Polish strains were classified into serogroups O10, O38, O36, O30, O17, O23, O9, O40, O49, O27, O5, O13, O24, O14, and O33. From the Swedish strains, 10 belonged to serogroup O10 and five to each of serogroups O38, O36, and O9. Therefore, none of the O-serogroups was predominant. The majority of the serotyped clinical strains possess acidic O-antigens containing uronic acids and various acidic non-carbohydrate substituents. In immunoblotting, antisera cross-reacted with both O-antigen and core of LPSs. The core region of 19 LPSs bound a single serum, and that of 12 LPSs bound more than two sera. Following bioinformatic analysis of the available sequences, a molecular approach to the prediction of Proteus core oligosaccharide structures was proposed. The identification of the core type of P. mirabilis R110, derived from a serogroup O3 wild strain, using restriction fragments length polymorphism analysis of galacturonic acid transferase is shown as an example. In summary, the most frequent O-serogroups among P. mirabilis UTI stains were identified. The diversity of serological reactions of LPSs is useful for serotyping of P. mirabilis clinical isolates. A possible role of the acidic components of O-antigens in UTI is discussed.

Verification of the effectiveness of SCAR (sequence characterized amplified region) primers for the identification of Polish strains of Fusarium culmorum and their potential ability to produce B-trichothecenes and zearalenone

Rapid and sensitive methods to detect Fusarium culmorum and trichothecene and zearalenone producing strains in food and feed are valuable in predicting potential contamination. In this study the effectiveness of primers, recommended in the literature, for species identification of F. culmorum and basic genes encoding for mycotoxin production was tested. A total of 68 isolates of F. culmorum were collected from cereals and potato between 2005 and 2008 from different Polish provinces. It was shown that from among the four primer pairs enabling the identification of F. culmorum, and therefore also to establish its presence in the material, only primers Fc01F/Fc01R seem to be fully effective in the case of Polish strains. Determination of material contamination by F. culmorum, however, is only a first step in determining food safety. It is also extremely important to identify genes encoding the potential ability to produce mycotoxins. It was shown that three pairs of primers (tox5-1/tox5-2, HATriF/HATriR and Tri5F/Tri5R) enable a fully effective identification of the presence of the Tri5 gene responsible for producing trichothecenes. Determination of the DON-chemotype, and thus identification of the strains of F. culmorum potentially producing deoxynivalenol, is enabled equally by MinusTri7F/MinusTri7F, Tri7F/Tri7DON and Tri13F/Tri13DONR. However, a determination of the NIV-chemotype, and thus identification of the strains potentially producing nivalenol, is enabled by Tri7F/Tri7R, Tri7F/Tri7NIV and Tri13NIVF/Tri13R. The potential ability of isolates to produce ZEA can be determined to the same degree in assay with PKS4-PS.1/PKS4-PS.2 and F1/R1.

One-year molecular survey of astrovirus infection in turkeys in Poland

The presence of turkey astrovirus (TAstV) was monitored in meat-type turkey flocks in Poland in 2008. Clinical samples (10 individual faecal swabs/flock) from 77 flocks aged 1-19 weeks were collected from different regions of the country. RT-PCR experiments were performed for detection and molecular characterization of TAstV using four sets of primers within the RdRp gene (ORF1b). The prevalence of astrovirus was 34/77 (44.15%) in the flocks tested. TAstV type 2 was associated with 30 of 77 infections (38.9%), either alone or in mixed infections; TAstV type 1 was detected in 9 of 77 flocks (11.6%), either alone or in mixed infections; ANV was detected only in one flock (1.29%) by sequence analysis during this study. Phylogenetic analysis revealed genetic variability in the TAstV strains that were isolated. Some of Polish TAstV-2 strains were genetically related to the North American isolates; however, most of them formed a distinct subgroup of “European” isolates, suggesting their separate origin or evolution. Additionally, due to the high variability of the TAstV sequences, the most suitable method for TAstV typing seems to be sequencing.

Molecular characteristics of Polish field strains of Marek's disease herpesvirus isolated from vaccinated chickens.

BackgroundTwenty-nine Marek's disease virus (MDV) strains were isolated during a 3 year period (2007-2010) from vaccinated and infected chicken flocks in Poland. These strains had caused severe clinical symptoms and lesions. In spite of proper vaccination with mono- or bivalent vaccines against Marek's disease (MD), the chickens developed symptoms of MD with paralysis.Because of this we decided to investigate possible changes and mutations in the field strains that could potentially increase their virulence. We supposed that such mutations may have been caused by recombination with retroviruses of poultry - especially reticuloendotheliosis virus (REV).MethodsIn order to detect the possible reasons of recent changes in virulence of MDV strains, polymerase chain reaction (PCR) analyses for meq oncogene and for long-terminal repeat (LTR) region of REV were conducted. The obtained PCR products were sequenced and compared with other MDV and REV strains isolated worldwide and accessible in the GeneBank database.ResultsSequencing of the meq oncogene showed a 68 basepair insertion and frame shift within 12 of 24 field strains. Interestingly, the analyses also showed 0.78, 0.8, 0.82, 1.6 kb and other random LTR-REV insertions into the MDV genome in 28 of 29 of strains. These genetic inserts were present after passage in chicken embryo kidney cells suggesting LTR integration into a non-functional region of the MDV genome.ConclusionThe results indicate the presence of a recombination between MDV and REV under field conditions in Polish chicken farms. The genetic changes within the MDV genome may influence the virus replication and its features in vivo. However, there is no evidence that meq alteration and REV insertions are related to the strains' virulence.

Identification of the Polish strains of Chalara ovoidea using RAPD molecular markers

On the basis of morphological features and RAPD markers the strains of <em>Chalara ovoidea</em> found in Poland on planks and on stems of beech trees were identified. As reference strains the cultures taken from CBS Utrecht were employed; they were cultures CBS 354.76 and CBS 136.88. The amplification of genomic DNA was conducted using 10 primers (OPA01-OPA10), 7 of which (OPA01-OPA05, OPA09, OPA10) gave positive results. In total 42 fragment of DNA (bands) were obtained. In case of primers OPA03, OPA04, OPA05, and OPA09 all obtained fragments for analyzed strains were fully monomorphic. This means, that no genetic variability was found using the above mentioned primers. Low genetic variability was ascertained in the analysis of frequency of occurrence of DNA fragments using other primers, namely OPA01, OPA02, and OPA10. The matrix and dendrogram of genetic affinities among different strains of <em>Chalara</em>, calculated using the Jaccard’s similarity coefficient suggested, that the most similar strains are the ones coming from Poland (HMIPC 16136 and HMIPC16664) as well as the strain CBS 136.88, while somewhat different from them is the strain CBS 354.76. To determine, how exactly did the dendrogram reflect genetic affinity among analyzed strains, the Mantel’s test was employed. The correlation coefficient amounted to 0.78, suggesting that the strains under study had been grouped properly. The results showed, that the fungal strains found in southern Poland represent the species Chalara ovoidea.

Genetic analysis and phylogenetic comparison of Black queen cell virus genotypes

Phylogenetic analysis of 22 Black queen cell virus (BQCV) genotypes collected from honeybee colonies in Poland, Austria and Hungary was performed on a partial helicase enzyme coding region (ORF1) and on a partial structural polypeptide coding region (ORF2). While the phylogeny based on the ORF2 region showed – with the exception of one strain from Poland – clustering of the genotypes corresponding to their geographic origin, the ORF1-based tree exhibited a completely different distribution of the Polish strains: three of them clustered within a branch clearly separated from all other central European BQCVs, while four other Polish strains remained well within the central European BQCV genotypes. In order to investigate this discrepancy in more detail, the nearly complete genome sequences of the three differing Polish strains were determined, together with one Hungarian sample. The sequences were aligned to each other and to the reference strain from South-Africa. Comparison of the different genome regions revealed that the 5′-UTR and the intergenic regions of the BQCV genome are highly conserved with longer homologous sections. ORF1 (non-structural protein coding region) was found more variable compared to ORF2 (structural protein coding region). The 5′-proximal third of ORF1 was particularly variable and contained several deletions/insertions. The sudden changes in the similarity levels of BQCV strains in different genomic regions are indicative of preceding recombination events.

Genetic variance of Derzsy�s disease strains isolated in Poland

The aim of this study was the assessment of the genetic variance of Derzy's disease (GPV) strains isolated from cases occurring in Poland. The nucleotide and predicted aminoacid sequences of VP2 and VP3 surface proteins of the Polish GPV strains were compared with other strains previously isolated in Hungary, France, Germany, China and Taiwan. The observed genetic variance of the aminoacid sequence within the group of Polish strains was low and reached 5% of the overall analysed sequence. Considerable differences in aminoacid sequence were found in the case of Polish field GPV strains and Muscovy duck parvovirus strain MDPV FM which was also analysed in this study. The conducted investigations confirmed the presupposition that Polish GPV strains and strains previously isolated in Hungary and France share a common origin.

Genetic variation in Polish strains of Gremmeniella abietina

SummaryThirty‐nine strains of Gremmeniella abietina were isolated between 1980 and 2005 from diseased or symptomless Pinus sylvestris and Pinus nigra, or sporadically Pinus jeffreyi and Pinus armandii from four regions of Poland with varying climatic conditions. Thirty‐five of the strains were genetically similar to the G. abietina A type found in Scandinavia, whereas four were similar to the B type. On the basis of random amplified microsatellite markers, very high intrapopulation and interpopulation genetic variation was detected among the strains. The average value of the Jaccard genetic similarity coefficients among strains was 0.56 for A type and 0.47 for B type, and the monomorphic loci partition was small, at 14% of all analysed loci for the A type. The degree of genetic variation of the fungal strains within each of the four regions was similar, showing no significant differences. The Jaccard coefficient for the strains isolated from P. sylvestris and P. nigra differed significantly, at 0.57 and 0.54 respectively. The genetic distance among A type strains from the investigated regions, expressed using Nei’s coefficient, was not correlated with geographic distance; however, it was highly dependent on elevation (correlation coefficient r = 0.92).

The sequence and model structure analysis of three Polish peanut stunt virus strains

Peanut stunt virus (PSV) belongs to the Cucumovirus genus of the family Bromoviridae and is widely distributed worldwide, also in Poland. PSV is a common pathogen of a wide range of economically important plants. Its coat protein (CP), similarly as in other viruses, plays an important role in many processes during viral life cycle and has great impact on the infectivity. In this study, we present the results of sequence-structure analysis of CP derived from three Polish strains of PSV: PSV Ag, G, and P. Sequences were determined using RT-PCR amplification followed by sequencing and compared with each other and also with CP from other known PSV viruses. We analyzed their phylogenetic relationship, based on CP sequence, using bioinformatic tools as well as their spatial model using homology-modeling approach with combination of ROSETTA algorithm for de novo modeling. We compared our model with those recently obtained for other cucumoviruses including PSV-Er. Our results have shown that all Polish strains probably belong to the first subgroup of PSV viruses. Homology level between strains Ag and G proved very high. Using theoretical modeling approach we obtained a model very similar to the one resolved previously with the differences caused by slightly different amino acid sequence. We have also undertaken an attempt to analyze its distant regions; however, results are not unequivocal. Analysis of symptoms and their correlation with specific amino acid position was also performed on the basis of results published elsewhere. The definite interpretation is impeded by the presence of satellite RNAs in Ag and P strains modulating symptoms' severity, though.

Genetic variability and differentiation of rainbow trout (Oncorhynchus mykiss) strains in northern and Eastern Europe

Variation of 10 microsatellite loci was analyzed in 12 rainbow trout strains reared in northern and Eastern Europe (Finland, Denmark, Sweden, Norway, Estonia and Poland). For comparison, two wild populations from Canada and a farmed strain from USA (Shasta strain from California) were analyzed. In majority of European strains, the level of variability, measured as the average allele richness and observed heterozygosity, was similar to that of Shasta strain with the exception of two Polish strains which exhibited significantly lower variability and elevated level of inbreeding. Only 0.9% of the total genetic variation in farmed strains was accounted for by differences between the countries of origin, 13.7% was due to differentiation among the strains within the countries and 85.5% was due to variation within strains. The farmed strains were moderately differentiated (average FST=0.14) and the individual fish could be assigned to their strain of origin with an average of 90% accuracy. The European strains were genetically more similar to the Shasta strain than to the Canadian wild populations which provide support to their ancestry from rainbow trout populations in California.

Characterization ofAeromonas caviae andA. veronii by standardized cellular protein electrophoretic patterns

Aeromonas caviae and A. veronii recovered from clinical and environmental samples were characterized by SDS-PAGE of whole cell proteins. All strains were typable and showed unique banding patterns. A high intra-specific diversity within these two microorganisms was revealed. Separation of the Polish strains from the Hong-Kong isolates was observed. A. caviae and A. veronii were not distinguishable with respect to their ecological origin. However, strains with very similar protein patterns could dominate in a specific habitat.

Effect of genetics and temperature on carp juvenile survival in ponds of the temperate climat

In a temperate climate the survival of carp larvae is limited by the pronounced cooling that usually occurs in the period of early stages of larval development, i.e. during the late spring. On the basis of previously obtained results it was assumed that years favourable for the survival of juvenile carp occur when the water temperature in the pond decreases from about 20 °C to about 14 °C more than 10 days after pond stocking. The unfavourable years are those with a temperature decrease occurring earlier. In a shallow nursery pond the cooling causes severe temperature drops that can create lethal conditions for the carp larvae. The frequent temperature decreases encouraged the seeking of carp strains and crossbreeds resistant to such changes. Polish, Hungarian, and French strains and also crossbreeds between them were considered. Under favourable thermal conditions the crossbreeds and strains showed distinctly higher average survival (p = 0.086). In each year the survival rate of the crossbreeds was higher (p = 0.013) although there was a pronounced variability in the survival rate of all breeds and crosses.