ABSTRACT
Ichthyophonosis is a disease caused by the mesomycetozoean parasite Ichthyophonus hoferi that affects a variety of fish species, including rainbow trout Oncorhynchus mykiss Walbaum. This disease is characterized by granulomatous lesions and necrosis in various organs, which can have severe impacts on the health and welfare of the fish. Ichthyophonosis has been found in several parts of the world, including Europe, and is a significant concern in the aquaculture industry and for populations of wild marine fishes. The rainbow trout is a widely cultured salmonid species in many countries, including Serbia. Although the presence of I. hoferi in rainbow trout has been reported in several countries, it has never been documented in Serbia. In this article, we report the first case of ichthyophonosis in rainbow trout in Serbia.
Subject(s)
Aquaculture , Fish Diseases , Mesomycetozoea Infections , Mesomycetozoea , Oncorhynchus mykiss , Animals , Fish Diseases/parasitology , Fish Diseases/epidemiology , Serbia/epidemiology , Mesomycetozoea Infections/epidemiology , Mesomycetozoea Infections/parasitology , Mesomycetozoea/isolation & purificationABSTRACT
Mass mortality of farmed 1 yr old common carp Cyprinus carpio occurred at a carp farm in April 2022. In addition to high mortality, diseased fish exhibited papillomatous growths on the skin and fins, characteristic of carp pox. To investigate a possible viral cause, tissue samples were collected and nucleic acid was extracted using standard procedures. In a pooled sample from the gills and kidneys, carp edema virus (CEV) was detected by real-time PCR. In a skin tissue sample with papillomatous growths, cyprinid herpesvirus 1 (CyHV1) was detected by a conventional PCR targeting a conserved region of the DNA polymerase of cyprinid herpesviruses. PCR products were visualized through agarose gel electrophoresis, and the presence of CyHV1 DNA was confirmed by Sanger sequencing. This represents the first molecular confirmation of CyHV1 in common carp in Serbia.
Subject(s)
Carps , Fish Diseases , Herpesviridae Infections , Herpesviridae , Animals , Serbia/epidemiology , Herpesviridae/genetics , Real-Time Polymerase Chain Reaction/veterinary , Fish Diseases/epidemiology , Herpesviridae Infections/epidemiology , Herpesviridae Infections/veterinaryABSTRACT
In the manufacturing sector, improving energy efficiency in small and medium-sized enterprises (SMEs) is typically more challenging than in larger companies. Although the barriers to and drivers of energy efficiency measures (EEMs) are relatively well researched and identified in the literature, little attention has been paid to the factors that influence how SMEs perceive them. This study uses a sample of 220 manufacturing SMEs in Slovenia to econometrically assess the relevance of a comprehensive set of firm-, business-, energy- and energy efficiency-related characteristics to the barriers to and drivers of EEMs identified in the literature. The objective of this study is to identify which factors influence the importance of various barriers and drivers while accounting for firm heterogeneity. The results show that among the most influential factors of perceived barriers are energy intensity and export orientation, which are associated with the lower importance of perceived barriers, while debt works in the opposite direction. Surprisingly, firm size does not have an impact on barriers, except for one - the additional risk involved in EE investments, whereas it impacts several drivers. A low level of competition in the market and ownership of the firm's premises also contribute to the lower intensity of perceived barriers. In terms of the perceived importance of drivers, the most influential factors are firm size, the presence of an energy-responsible person in the firm and the company's employee energy efficiency awareness programme. Among the approaches to improve energy efficiency, the introduction of an energy policy or energy management system and certifications have the greatest influence on removing barriers, while energy consulting is not found to be significant. Furthermore, the importance of drivers is mainly positively associated with energy audits. These results provide useful policy implications for how to address the energy efficiency gap in manufacturing SMEs by targeting factors that would most effectively lower barriers to and strengthen drivers of energy efficiency.
ABSTRACT
Introduction: Swine influenza A viruses (swIAVs) are characterised by high mutation rates and zoonotic and pandemic potential. In order to draw conclusions about virulence in swine and pathogenicity to humans, we examined the existence of molecular markers and accessory proteins, cross-reactivity with vaccine strains, and resistance to antiviral drugs in five strains of H1N1 swIAVs. Material and Methods: Amino acid (AA) sequences of five previously genetically characterised swIAVs were analysed in MEGA 7.0 software and the Influenza Research Database. Results: Amino acid analysis revealed three virus strains with 590S/591R polymorphism and T271A substitution within basic polymerase 2 (PB2) AA chains, which cause enhanced virus replication in mammalian cells. The other two strains possessed D701N and R251K substitutions within PB2 and synthesised PB1-F2 protein, which are the factors of increased polymerase activity and virulence in swine. All strains synthesised PB1-N40, PA-N155, PA-N182, and PA-X proteins responsible for enhanced replication in mammalian cells and downregulation of the immune response of the host. Mutations detected within haemagglutinin antigenic sites imply the antigenic drift of the five analysed viruses in relation to the vaccine strains. All viruses show susceptibility to neuraminidase inhibitors and baloxavir marboxil, which is important in situations of incidental human infections. Conclusion: The detection of virulence markers and accessory proteins in the analysed viruses suggests their higher propensity for replication in mammalian cells, increased virulence, and potential for transmission to humans, and implies compromised efficacy of influenza vaccines.
ABSTRACT
To achieve ambitious energy-climate targets, all EU member states have introduced policies to support the market introduction of renewable energy sources (RES) generation. Motivated to close the gap of the merit order effect (MOE) in less mature Central and South East European electricity markets, we empirically confirm economic theory predictions that in the short run, an increase in RES generation reduces electricity prices. The merit order effect is initially econometrically confirmed and quantified. Different econometric model specifications are estimated to differentiate the MOE caused by wind and solar generation and to differentiate the MOE on high-load and low-load days. In addition, we simulate the adjustment of the realised day-ahead electricity prices to the no-RES generation scenario. Modern statistical methods are applied to bridge the gap in the limited public data availability to solve simulation models used in the power system or agent-based simulations. A family of data mining algorithms is applied for the merit order estimation used in the dynamic adaptation of the generation mix to the omitted RES generation. The estimated energy imbalance caused by the excluded RES generation is therefore compensated by the additional conventional generation dispatch according to the estimated power plant merit order. The estimated supply curves for each generation technology assist the reasoning behind the established MOE in econometric models. Based on our findings, policymakers should prioritise policies that facilitate the integration of RES into their electricity markets, which would in turn accelerate energy transition. With increasingly growing shares of renewables in the system, the governments need to rethink the support scheme, where the emphasis should be placed on efficiently integrating renewables in the power system by taking into account temporal and spatial dimensions.
Subject(s)
Electricity , Renewable Energy , Greece , Hungary , RomaniaABSTRACT
Spring viraemia of carp (SVC) is an infectious disease responsible for severe economic losses for various cyprinid species, particularly common carp (Cyprinus carpio carpio). The causative agent is the Rhabdovirus carpio or SVC virus (SVCV), a member of the Sprivivirus genus, within the Rhabdoviridae family. Phylogenetically, SVCV is divided into four genogroups (SVCV a, SVCV b, SVCV c and SVCV d), which have a reasonable correlation with the geographical distribution of the virus. In the late twentieth century, the disease was widespread in Serbian aquaculture and caused massive deaths in common carp. This study aimed to molecularly characterize the circulating SVCV isolates in Serbia over a 17-year period. The genetic relationships between 21 SVCV isolates from common carp and rainbow trout in Serbia between 1992 and 2009 were determined based on the partial nucleotide sequence of the glycoprotein gene (G gene). The phylogenetic analysis showed that the dominant SVCV isolates in Serbia belong to the SVCV d genogroup, with only one isolate belonging to genogroup SVCV b. The SVCV strains circulating in Serbia exhibited high homogeneity, as several isolates shared 100% similarity within these genogroups. Most Serbian isolates belonged to SVCV d1 and d2 subgroups, with one isolate notably different and included in a new subgroup SVCV d5. Understanding the SVCV genetic variants circulating in Serbia would be helpful in future epizootic investigations.
Subject(s)
Carps , Fish Diseases , Rhabdoviridae Infections , Rhabdoviridae , Animals , Viremia , Phylogeny , Serbia/epidemiology , Fish Diseases/epidemiology , Rhabdoviridae Infections/epidemiology , Rhabdoviridae Infections/veterinaryABSTRACT
Swine influenza presents a very important health and economic issue in pig productions worldwide. Viruses that cause the disease are genetically very diverse but usually belong to the H1N1, H1N2 and H3N2 subtype of influenza A viruses. In this study, we sequenced and analyzed the full genome of viruses detected in swine from seven commercial farms. Through the analysis of the complete sequences of internal gene cassette together with previously characterized HA and NA genes we found three different genotypes amongst five completely sequenced viruses. Two viruses possessed a completely H1avN1 genotype (40%) and belonged to the H1avN1 lineage, which is prevalent in European swine populations. The other three viruses have arisen through the reassortment of the genes of H1avN1 and H1N1pdm09 lineages. In one sample we detected coinfection with viruses of H3N2 subtype with genes of H1avN1, H1N1pdm09 and A/swine/Gent/1/1984-like H3N2 lineages that presents a potential environment for the generation of a triple reassortant virus. The presence of the H1N1pdm09 origin M gene in this sample implies the potential risk of the introduction of these viruses into the human population. Phylogenetic analysis of internal gene cassette revealed slower evolution within genes of H1N1pdm09 lineage than those of H1avN1 lineage.
Subject(s)
Influenza A Virus, H1N1 Subtype , Influenza A virus , Humans , Animals , Swine , Influenza A virus/genetics , Serbia/epidemiology , Farms , Influenza A Virus, H3N2 Subtype/genetics , PhylogenyABSTRACT
Sleeping disease is a highly infectious viral disease caused by salmonid alphavirus subtype 2 (SAV2 FW), affecting mainly rainbow trout Oncorhynchus mykiss farmed in freshwater. During March to May 2014, disease episodes with clinical signs of sleeping disease in rainbow trout fingerlings occurred almost simultaneously in 2 trout farms located in Bosnia and Herzegovina (BiH) and Serbia. The infection of rainbow trout with SAV2 FW in 2 farms was confirmed by virus isolation and molecular methods. This is the first isolation and molecular characterization of SAV2 FW in BiH and Serbia.
Subject(s)
Alphavirus Infections , Alphavirus , Fish Diseases , Oncorhynchus mykiss , Alphavirus Infections/epidemiology , Alphavirus Infections/veterinary , Animals , Bosnia and Herzegovina/epidemiology , Fish Diseases/epidemiology , SerbiaABSTRACT
Hepatitis E virus (HEV), the zoonotic agent of infectious hepatitis, is present in swine farms in different geographical areas. Little is known about the mechanism of liver damage and type of local immune response by HEV in swine. Therefore, the aim of this study was to determine the morphological and immunophenotypic characteristics of hepatic lesions caused by hepatitis E virus in naturally infected swine. In this study, liver samples of 12 slaughtered 10 weeks old pigs which were RT-PCR positive for HEV RNA in rectal swab samples have been used. Livers were macroscopically examined and samples were taken for histopathological, immunohistochemical (CD3, CD79α and TGF-ß1), semiquantitative, morphometric analysis, RT-nested-PCR, PCR and bacteriological analysis. Microscopically, mild and moderate multifocal lymphoplasmacytic hepatitis was observed. Apoptotic bodies were observed as areas of focal eosinophilic condensation in the cytoplasm of 33.33% liver samples, while in 16.67% liver samples portal fibrosis was detected. Immunohistochemically, portal and lobular lymphocytes in the mononuclear liver infiltrate were predominantly CD3+ T cells (234.80 ± 79.98). An intense TGF-ß1 positive reaction was observed within the mononuclear cell infiltrate as well as polymorphonuclear cells in liver samples with apoptosis of hepatocytes. In all 12 tested liver samples HEV RNA was detected by RT-nested-PCR. HEV is noncytopathic, and this finding provides further evidence for an immune mediated pathogenesis in hepatitis E virus infection in swine. Also, the role of CD3+ cells in hepatocyte damage is clearly demonstrated.
Subject(s)
Hepatitis E virus , Swine Diseases , Animals , Hepatitis E virus/genetics , Liver/pathology , Phylogeny , RNA , Swine , Transforming Growth Factor beta1/geneticsABSTRACT
Rift Valley fever (RVF) is an arboviral zoonosis that primarily affects ruminants but can also cause illness in humans. The increasing impact of RVF in Africa and Middle East and the risk of expansion to other areas such as Europe, where competent mosquitos are already established, require the implementation of efficient surveillance programs in animal populations. For that, it is pivotal to regularly assess the performance of existing diagnostic tests and to evaluate the capacity of veterinary labs of endemic and non-endemic countries to detect the infection in an accurate and timely manner. In this context, the animal virology network of the MediLabSecure project organized between October 2016 and March 2017 an external quality assessment (EQA) to evaluate the RVF diagnostic capacities of beneficiary veterinary labs. This EQA was conceived as the last step of a training curriculum that included 2 diagnostic workshops that were organized by INIA-CISA (Spain) in 2015 and 2016. Seventeen veterinary diagnostic labs from 17 countries in the Mediterranean and Black Sea regions participated in this EQA. The exercise consisted of two panels of samples for molecular and serological detection of the virus. The laboratories were also provided with positive controls and all the kits and reagents necessary to perform the recommended diagnostic techniques. All the labs were able to apply the different protocols and to provide the results on time. The performance was good in the molecular panel with 70.6% of participants reporting 100% correct results, and excellent in the serological panel with 100% correct results reported by 94.1% of the labs. This EQA provided a good overview of the RVFV diagnostic capacities of the involved labs and demonstrated that most of them were able to correctly identify the virus genome and antibodies in different animal samples.
Subject(s)
Rift Valley Fever/diagnosis , Animals , Black Sea , Culicidae , Europe , Genome, Viral , Humans , Laboratories , Mediterranean Sea , Rift Valley Fever/virology , Rift Valley fever virus/genetics , RuminantsABSTRACT
Infectious haematopoietic necrosis virus (IHNV) is the causative agent of infectious haematopoietic necrosis (IHN), a disease of salmonids responsible for great economic losses. The disease occurs in most parts of the world where rainbow trout is reared but has not been previously reported in North Macedonia. In this study, 150 pooled samples in total, each consisting of organ mix of 10 freshly killed rainbow trout Oncorhynchus mykiss, were collected from 50 trout farms by the Food and Veterinary Agency of North Macedonia as part of the annual surveillance plan for IHN and viral haemorrhagic septicaemia (VHS) control. Screening of samples was done by cell culture and real-time RT-PCR (qRT-PCR). All 150 tested samples were VHS virus (VHSV) qRT-PCR negative. Two samples from different trout farms were IHNV qRT-PCR positive. On cell culture, 1 IHNV qRT-PCR positive sample caused cytopathic effect after 2 passages on EPC cells. The virus, isolated from an asymptomatic rainbow trout fry, was identified by qRT-PCR and designated as MAKIHNV1. The phylogenetic reconstruction indicates that the isolated virus belongs to the European E genogroup, more specifically within the E-1 clade, and is similar to the German, Italian and Iranian isolates. This study has revealed for the first time the presence of IHNV in rainbow trout in North Macedonia. However, it is not possible to make interpretations about the source of infection from the phylogenetic analysis, and the origin of MAKIHNV1 remains unclear.
Subject(s)
Fish Diseases , Infectious hematopoietic necrosis virus , Oncorhynchus mykiss , Rhabdoviridae Infections/veterinary , Animals , PhylogenyABSTRACT
Porcine Kobuvirus (PKV) infection is very common in pigs throughout the world. Since it has never been investigated in Serbia, to contribute to the knowledge of Porcine Kobuvirus, its role, and distribution, we tested 200 samples from domestic pigs and wild boars. From domestic pigs, 10 fecal, 22 spleen and 68 serum samples, and 100 spleen samples from wild boars were tested. The virus prevalence determined by real-time RT-PCR in domestic pigs was 22% and in wild boars 6%. The phylogenetic analysis of 3D region revealed that Serbian strains are closest related to the Hungarian strain from wild boar from 2011. This is the first report on PKV in Serbia in domestic pigs and wild boars, implying its wide circulation. Although the infection could not be directly related to any clinical manifestation, the frequency of virus found in feces suggests viral affinity to the gastrointestinal tract. However, due to the rather ubiquitous presence of PKV, the clinical and pathological assessment have to be considered when PKV infection is diagnosed.
Subject(s)
Kobuvirus/isolation & purification , Picornaviridae Infections/veterinary , Swine Diseases/epidemiology , Animals , Female , Kobuvirus/classification , Kobuvirus/genetics , Phylogeny , Picornaviridae Infections/epidemiology , Picornaviridae Infections/virology , Polymerase Chain Reaction/veterinary , Prevalence , Serbia/epidemiology , Sus scrofa , Swine , Swine Diseases/virologyABSTRACT
Considering the intensive trading nowadays, the honey from the local market was tested for the presence of the six most common bee viruses. To prove the suitability of honey as a sample for the bee viruses detection, the set of different sample types taken directly from the hives we comparatively tested. The study included 30 samples of domestic and 5 samples of imported honey. Additionally, we tested 40 sets of samples including live bees, dead bees, and the honey taken from four apiaries for the evaluation of honey suitability for the virus detection, Two out of the six most common bee viruses were detected in the samples of honey from the market. Black queen cell virus (BQCV) genome was found in 24 domestic honey samples and Kashmir bee virus (KBV) genome was detected in one sample of imported honey. The nucleotide sequences of 24 BQCV isolates showed the highest identity (86.4%) with strains from Europe at the polyprotein gene, whilst the Serbian isolates between each other showed 98.5% similarity. By comparative testing of the different type of samples, in three out of four apiaries BQCV genome was detected in both bees and honey. Evaluating the suitability of honey for the detection of the viral disease by simultaneous testing of live, dead bees, and honey from the same hive, it was shown that the honey can be successfully used for the detection of BQCV. Since, as of yet, there has been no evidence of KBV circulation in Serbia, after its detection in imported honey, there is a substantial risk of its introduction and consequently the need for its surveillance. Therefore, the programs of bee diseases screening should be included in the regular control procedures for the international trade. In addition to this benefit, honey gives an opportunity to beekeepers for continuous monitoring of bees' health status.
ABSTRACT
Bovine viral diarrhea (BVD) is one of the most economically important diseases of cattle. With its very high prevalence, cattle kept on pastures become a source of the virus for the wildlife which, due to their susceptibility, then easily can serve as a source for re-infections of cattle. Therefore, we investigated the BVDV infection in Serbian wild boar and assessed the role of wild boar in BVDV epidemiology including possible spreading to domestic species. This study was based on examination of 50 spleen samples which were collected from wild boars located in Eastern Serbia during the hunting season 2016/2017. BVDV genome was detected in 4 of 50 samples (8%). Phylogenetic analysis based on 5'UTR revealed that BVDV strains from wild boars shared 100% identity. Belonging to the BVDV 1f subgenotype, the most common in cattle, we showed that BVDV infections of wild boar occurred as a result of either direct or indirect contact with domestic animals. Therefore, the occurrence of infectious disease in wildlife emphasizes the need to study the pathogens shared by wildlife and domestic animals by investigating the incidence of pathogens and disease patterns of those populations.