Schmallenberg disease is an infectious disease of cattle, sheep, and goats of viral aetiology caused by the Schmallenberg virus that belongs to the family
and the genus
. Schmallenberg disease is a ...vector-borne disease transmitted by midges from the genus
but also by other hematophagous insects. The disease has a seasonal character and most often occurs in the warm months, from late spring to autumn. In this study, we investigated the seroprevalence of Schmallenberg disease in sheep in the epizootic area of Belgrade in the period from 2017 to 2022. A total of 600 sheep serums from the serum bank were tested, 100 serum samples from each year. Sera were tested by commercial ELISA test for the detection of specific antibodies against the Schmallenberg virus. The results showed an average annual seroprevalence of 24.5% in sheep in the Belgrade area in these six years with an increasing trend predicted for the next years.
Until July 30
, 2019 when the first case of African swine fever (ASF) was confirmed, Serbia was a country free from ASF. After the owner reported atypical illness and death of a sow, the local ...veterinarian submitted the organ samples to the National Reference Laboratory for Classical Swine Fever (CSF) and African Swine Fever within the Institute of Veterinary Medicine of Serbia in Belgrade. Observed gross lesions included splenomegaly, serous edema of the wall of the gallbladder and hemorrhages in the enlarged portal lymph nodes, petechial hemorrhages on the kidney and epicardium, and petechial and echymotic hemorrhages on the mucosa of the urinary bladder. Results of real-time PCR confirmed that the cause of illness and death of the swine was African swine fever virus. The samples were sent for confirmation to the EU Reference Laboratory where it was confirmed that Serbian domestic pig virus isolates based on p72 belong to genotype II. In total, 270 pigs from 18 affected holdings were killed in the infected zones. According to the on-record data, mortality was 6.89%, whereas lethality reached 64.5%. Currently, an extensive surveillance program is being conducted, aiming to force passive surveillance. ASF in wild boar has not been confirmed so far.
A poxvirus named carp edema virus (CEV), is the causative agent of carp edema virus disease (CEVD), which is an emerging disease of global concern that may cause high rates of morbidity and mortality ...in ornamental koi and common carp and. Common carp (Cyprinus carpio) is the most important fish species for warm‐water aquaculture in Serbia. CEVD was first time detected in Serbia in 2017. During 2017-2020 period, increasing number of CEVD outbreaks in carp farms is reported. Carp were collected from farms in different regions of Serbia from 2017 to 2020. The fish were sampled for disease diagnosis because they exhibited lethargy and anorexia, which eventually led to mortality. Mortality started with clinical signs of hypoxia while fish swam slowly without escaping reactions. The gills were pale and covered with a thick mucus layer. In advanced cases, the lesions in the gills turned into a necrotizing form. A moderate to high amount of opportunistic freshwater bacteria were isolated from gills of diseased fish. By performing real-time PCR, CEV was detected in 38 samples of diseased carps from 21 carp farms. These outbreaks further confirm the spread of CEVD and the need for practitioners to be vigilant for outbreaks of this disease. To prevent further spreading of the disease, it is very important to introduce CEV testing before fish movement. To avoid further transmission of the virus to common carp populations in Serbia, testing of CEV should become part of fish disease surveillance programs. Fish health service should be aware of the presence of CEV in Serbia which may result in high losses in carp aquaculture. Action should be taken also to prevent transmission of CEV to carp populations in open waters.
Pigs are very important for the epidemiology of influenza A viruses, being commonly infected with the lineages of most adapted H1N1, H3N2, H1N2 swine subtypes. Epidemiological complexity of swine ...influenza is increasing by a periodic spillover of human or avian viruses in the pig population when genetic shifts can occur. The objectives of this research were to determine the presence of the influenza A virus in nasal and tracheobronchial swabs and lung tissue samples of ill and dead pigs on commercial farms, to determine circulating subtypes and characterize them through the phylogenetic analysis of hemagglutinin (HA) and neuraminidase (NA) genes. A total of 255 samples collected from 13 farms were analyzed by means of real-time RTPCR. The genome of influenza A virus was detected in 24 samples, which represented a 61.5% prevalence at the farms level (influenza A virus was confirmed in 8 out of 13 farms included in this study). Based on HA and NA gene sequences of 8 viruses, the circulation of H1N1 and H3N2 subtypes of influenza A viruses were determined. In addition, one farm exhibited a time separated circulation of H1N1 and H3N2 virus subtypes. Using Influenza Research Database, our viruses of the H1 subtype were classified into 1C.2.1 and 1A.3.3.2. clade. Based on the nucleotide sequences of HA genes, three viruses of the H1N1 subtype belong to the H1N1pdm09 lineage, and the other four to Eurasian “avian-like” H1avN1 lineage; while based on NA genes sequences, these seven viruses belong to Eurasian “avian-like” H1avN1 lineage. Both HA and NA genes of the virus of the H3N2 subtype belonged to the A/swine/ Gent/1/1984-like H3N2 lineage.
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.
Amino acid (AA) sequences of five previously genetically characterised swIAVs were analysed in MEGA 7.0 software and the Influenza Research Database.
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.
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.
STURGEON DISEASES IN AQUACULTURE Radosavljević, Vladimir; Milićević, Vesna; Maksimović-Zorić, Jelena ...
Archives of Veterinary Medicine,
09/2019, Volume:
12, Issue:
1
Journal Article
Peer reviewed
Open access
Sturgeon aquaculture is economically important in many countries, for both meat and caviar production. Sturgeon is the common name for 27 species of fish belonging to the family Acipenseridae. Among ...them, only the sterlet (Acipenser ruthenus) and the Siberian sturgeon (Acipenser baerii) completes the lifecycle in fresh water. In Serbia, in the last few years, aquaculture enterprises have shown more interest in farming these fish species. Also, the importance of sturgeon aquaculture grows due to the rapid decrease of wild populations caused by overfishing, water pollution and destruction of habitat. The development of sturgeon aquaculture activities has been accompanied by the disease outbreaks, and possibility of the emergence and rapid dissemination of several infectious disease agents may represent serious problem in sturgeon aquaculture. Several viral, bacterial, fungal and parasitic diseases have been reported worldwide. Due to the limited knowledge about epizootiology and disease control methods, infectious diseases may represent a major challenge in sturgeon aquaculture. Moreover, none of the diseases reported in sturgeon are regulated in the World Organization for Animal Health (OIE) or European Union (EU) legislations. Due to the increasing interest in sturgeon aquaculture in Serbia present study is focused on the most important pathogens that may represent a threat to sturgeon aquaculture in Serbia.
Abstract
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.
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.
•PKV infection is common in both domestic pigs and wild boars in Serbia.•Serbian strains are closely related to the Hungarian one from 2011 from wild boar.•AConsidering the frequency of virus found in feces, its affinity to the gastrointestinal tract is evident.
Porcine respiratory coronavirus is an enzootic, viral, respiratory disease of pigs, which manifests with mild clinical signs, but it takes part in the etiopathogenesis of the porcine respiratory ...disease complex. The virus was first discovered in Belgium in 1984 as a deletion mutant of the transmissible gastroenteritis virus. The two viruses are strongly antigenically related which is why they cross-react in serological tests. In this study, we tested 276 serum samples from different categories of pigs using ELISA test, which allows differentiation between the porcine respiratory coronavirus infection and transmissible gastroenteritis. The seroconversion for coronavirus infection was determined in 80.4% of tested samples. Out of 222 positive samples, 219 samples (98.6%) were positive for porcine respiratory coronavirus antibodies, while 3 (1.01%) samples were positive for transmissible gastroenteritis virus antibodies. Depending on the production category, 97.7% of piglets, 83% of sows, and 35% of gilts tested positive for porcine respiratory coronavirus antibodies. In total, 2.3% of piglets tested positive for transmissible gastroenteritis virus antibodies. Taking into account the characteristics of the ELISA test, its sensitivity and specificity, this result can be considered a false positive, because of a cross-reaction between the porcine respiratory coronavirus antibodies and the transmissible gastroenteritis virus. Specific antibodies in other swine production categories against the transmissible gastroenteritis virus were not determined.
Bovine viral diarrhea virus infection in wild boar Milićević, Vesna; Maksimović-Zorić, Jelena; Veljović, LJubiša ...
Research in veterinary science,
August 2018, 2018-Aug, 2018-08-00, 20180801, Volume:
119
Journal Article
Peer reviewed
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.
•BVDV infection in the wild boars occurred as the result of their simultaneous exposure to the same source.•BVDV 1f infection of wild boars occurred as a result of either direct or indirect contact with domestic animals.•In the endemic situation, wild boar could threaten BVDV eradication programs in domestic cattle.•Infectious diseases should be investigated through pathogen incidence and disease patterns in wild and domestic animals.
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