Olga Zorman Rojs

Dr. Olga Zorman Rojs


Research Focus & Metrics

Academic Career Length

21Years (2006-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 September 2011 in Acta Veterinaria Hungarica
Verified
Journal Article
Closed access
OROlga Zorman Rojs
Olga Zorman Rojs
UKUroš Krapež
Uroš Krapež
BSBrigita Slavec
Brigita Slavec
RJRahela Juršič-Cizerl
Rahela Juršič-Cizerl
TPTea Poljanec
Tea Poljanec
A field study was performed to determine the efficacy of three commercially available vaccines against infectious bursal disease (IBD) in commercial broilers raised in a high IBD virus (IBDV) risk area. Live attenuated intermediate and intermediate plus vaccines were used in four flocks. Birds were vaccinated orally at the estimated vaccination time. Three broiler flocks were vaccinated subcutaneously with a turkey herpesvirus (HVT)-IBD vector vaccine at one day old. Evaluation of the efficacy of different vaccines was focused on humoral immune response, bursa/body weight (B/Bw) ratio, molecular detection of IBDV in ileocaecal tonsils and bursa of Fabricius, and production parameters. The serological results showed that although the uptake of all three vaccine strains was confirmed in the lymphoid organs, no significant antibody response to vaccination was detected in flocks vaccinated with intermediate and intermediate plus vaccines. A significant increase in antibody titres detected in flocks vaccinated with the vector vaccine indicated its ability to induce an immune response in birds with a high level of maternally derived antibodies. Observations obtained in this field trial did not confirm the expected reduction of the B/Bw ratio in flocks vaccinated with less attenuated vaccines. No significant differences were observed between birds vaccinated with the vector vaccine and those immunised with the intermediate plus vaccine. Very virulent IBDV was confirmed in the flock vaccinated with the intermediate vaccine. The infection induced reduced B/Bw and moderate mortality but did not affect the production parameters. Field infection was not detected in broilers vaccinated with the intermediate plus vaccine and the vector vaccine.

13 September 2021 in Animals
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Journal Article
Open access
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MKMarjan Kastelic
Marjan Kastelic
IPIgor Pšeničnik
Igor Pšeničnik
GGGordana Gregurić Gračner
Gordana Gregurić Gračner
NCNina Cebulj-Kadunc
Nina Cebulj-Kadunc
RKRenata Lindtner Knific
Renata Lindtner Knific
ADAlenka Dovč
Alenka Dovč
The influence of different stress parameters in racing pigeon flocks, such as the presence of diseases and environmental conditions at the time of the races, were described. A total of 96 racing pigeons from 4 pigeon flocks were examined, and health monitoring was carried out. No helminth eggs and coccidia were found. Trichomonas sp. was confirmed in subclinical form. Paramyxoviruses and avian influenza viruses were not confirmed, but circovirus infections were confirmed in all flocks. Chlamydia psittaci was confirmed in one flock. Blood samples were collected, and HI antibody titers against paramyxoviruses before and 25 days after vaccination were determined. To improve the conditions during racing and the welfare of the pigeons, critical points were studied with regard to stress factors during the active training season. Serum corticosterone levels were measured in the blood serum of four different categories of pigeons from each flock. Corticosterone levels were almost twice as high in pigeons from the category that were active throughout the racing season, including medium- and long-distance racing, compared to the other three categories that were not racing actively. Within five hours of the finish of a race, the average serum corticosterone level was 59.4 nmol/L in the most physically active category. The average serum corticosterone level in this category remained at 37.5 nmol/L one month after the last race.

1 March 2006 in Avian Diseases
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Journal Article
Closed access
UKUros Krapez
Uros Krapez
DBDarja Barlič-Maganja
Darja Barlič-Maganja
ITIvan Toplak
Ivan Toplak
PHPeter Hostnik
Peter Hostnik
OROlga Zorman Rojs
Olga Zorman Rojs
The presence of chicken anemia virus (CAV) in Slovenia was confirmed by inoculation of 1-day-old chickens without antibodies against CAV and isolation of the virus on the Marek's disease chicken cell-MSB1 line and by polymerase chain reaction (PCR). Experimental inoculation of 1-day-old chickens resulted in lower hematocrit values, atrophy of the thymus, and atrophy of bone marrow. CAV was confirmed by PCR in the thymus, bone marrow, bursa of Fabricius, liver, spleen, ileocecal tonsils, duodenum, and proventriculus. The nucleotide sequence of the whole viral protein (VP)1 gene was determined by direct sequencing. Alignment of VP1 nucleotide sequences of Slovenian CAV isolates (CAV-69/00, CAV-469/01, and CAV-130/03) showed 99.4% to 99.9% homology. The VP1 nucleotide sequence alignment of Slovenian isolates with 19 other CAV strains demonstrated 94.4% to 99.4% homology. Slovenian isolates shared highest homology with the BD-3 isolate from Bangladesh. Alignment of the deduced VP1 amino acids showed that the Slovenian isolates shared 100% homology and had an amino acid sequence most similar to the BD-3 strain from Bangladesh (99.6%) and were 99.1% similar to the G6 strain from Japan and the L-028 strain from the United States. The Slovenian isolates were least similar (96.6%) to the 82-2 strain from Japan. A phylogeneric analysis on the basis of the alignment of the VP1 amino acids showed that CAV isolates used in the study formed three groups that indicated the possible existence of genetic groups among CAV strains. The CAV isolates were grouped together independent of their geographic origin and pathogenicity.

1 March 2019 in Journal of Applied Poultry Research
Verified
Journal Article
Open access
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OROlga Zorman Rojs
Olga Zorman Rojs
IZIrena Zdovc
Irena Zdovc
ADAlenka Dovč
Alenka Dovč
JŽJaka Žgajnar
Jaka Žgajnar
BSBrigita Slavec
Brigita Slavec
JAJerneja Avguštin Ambrožič
Jerneja Avguštin Ambrožič
SUMMARY. The purpose of the study was to investigate the presence, distribution and dynamics of extended-spectrum beta-lactamases (ESBL) and plasmid-mediated A

1 September 2010 in Avian Diseases
Verified
Journal Article
Closed access
UKUros Krapez
Uros Krapez
ASAdela Fratnik Steyer
Adela Fratnik Steyer
BSBrigita Slavec
Brigita Slavec
DBDarja Barlič-Maganja
Darja Barlič-Maganja
ADAlenka Dovč
Alenka Dovč
OROlga Zorman Rojs
Olga Zorman Rojs
Fourteen avian paramyxovirus type 1 (APMV-1; Newcastle disease) viruses isolated from dead free-living and domestic pigeons in Slovenia between 2000 and 2008 were analyzed by a molecular characterization of a part of the fusion protein gene, which included the region encoding the fusion protein cleavage site. Phylogenetic analysis indicated that the Slovene pigeon paramyxovirus type 1 (PPMV-1) viruses do not cluster together but instead are divided into two groups--4bi and 4bii--of sublineage 4b. Nine Slovenian strains were placed in group 4bii. Five other strains clustered together with PPMV-1 from group 4bi. The sequence of the fusion protein cleavage site of all Slovenian strains was typical for pathogenic APMV-1. The 112RRQKRF117 motif was present in the strains from group 4bii, whereas strains from group 4bi displayed the 112GRQKRF117 motif.

1 June 2008 in Acta Veterinaria Hungarica
Verified
Journal Article
Closed access
OROlga Zorman Rojs
Olga Zorman Rojs
UKUroš Krapež
Uroš Krapež
BSBrigita Slavec
Brigita Slavec
SMSara Mankoč
Sara Mankoč
RJRahela Jurišič-Cizerl
Rahela Jurišič-Cizerl
DBDarja Barlič-Maganja
Darja Barlič-Maganja
In 2004 and then in 2006 several outbreaks of infectious bursal disease (IBD) were reported in broiler and broiler breeder flocks in Slovenia. In this report ten recently emerged IBD viruses (IBDV) were characterised by sequence analysis of the VP2 hypervariable region and compared to previous Slovene IBDV strains from 1995/1996 and to some representative serotype 1 IBDV strains of different pathotypes. On the basis of nucleotide and amino acid identities, phylogenetic analyses and the presence of very virulent IBDV (vvIBDV) conserved amino acid substitutions, all Slovene isolates from recent outbreaks were identified as vvIBDV. Although some unique nucleotide exchanges and amino acid substitutions have been observed, the results of this study indicated that recent vvIBDV isolates are closely related with those from outbreaks in the 1990s. However, acute IBD has not been reported in commercial flocks in Slovenia for some years. This could lead to the conclusion that poor biosecurity and relaxed vaccination could be responsible for the re-emergence of vvIBDV.