Pathogenicity assessment of a bovine viral diarrhea virus type 1l (BVDV-1l) strain in experimentally infected calves.

Bovine viral diarrhea is a widespread and economically important viral disease for livestock which can cause clinically diverse manifestations. The number of established BVDV subgenotypes has increased, not only the serological relationships of recently described subgenotypes but virulence and pathogenic characteristics have not yet been mostly elaborated. The dominant BVDV subgenotype in Turkiye was elaborated to be BVDV-1l, that involves more than half of field strains and there is no scientific data to identify the pathogenicity of this strain so far. This study investigated the pathogenicity of a selected field strain (TR-72) from subgenotype BVDV-1l. Experimental infection was implemented by intranasal inoculation of the strain TR-72 (10 ×105.5) to four young calves which were previously not vaccinated and were free both for BVDV antibodies and antigens. Clinical changes as well as blood parameters, body temperature, and viremia were monitored for 14 days. Only mild clinical signs associated with respiratory signs of BVDV infection were observed. Detected clinical signs included nasal discharge, conjunctivitis, cough, fatigue, high rectal temperature reaching 40.7 â„ƒ, and white blood cell counts depression started from the 2nd day and 40.4% decreased between the 12th and 14th days post-infection (poi). The presence of viremia was investigated by virus isolation, RT-PCR, and real-time RT-PCR from blood samples. The efficiency of experimental infection was established not only by observed clinical signs but also by virus isolation from blood leukocytes between the 5th and 8th days poi., virus detection was obtained by real-time PCR between the 3rd - 13th days poi. Besides, the recorded mild clinical signs, high fever, long duration of viremia , and high decrease in blood parameters obtained in this study, it was shown that the noncytopathogenic BVDV-1l strain TR-72 has a moderate virulence in naïve cattle.

Characterization of bovine rotavirus isolates from diarrheic calves in Türkiye.

BACKGROUND: Neonatal calf diarrhea, which is the most common cause in calf deaths, leads to significant economic losses in dairy farming around the world. Diarrhea develops due to infectious and non-infectious reasons. Group A Rotaviruses (RVA) are the leading and predisposing factor for acute neonatal gastroenteritis. METHODS AND RESULTS: In this study, 20 diarrheic fecal samples were collected from one farm in Balikesir province of Turkey. During virus isolation, a total of 2 stool samples were detected to produce cytopathogenic effects in MA-104 cell line. The two samples (RV-36, RV-38) were tested positive with antigen ELISA kits detecting RVA antigens. In order to detect the presence of rotavirus viral nucleic acid in cell supernatants, VP6 gene region-specific RT-PCR test was performed and the samples RV-36 and RV-38 were positive for RVA viral nucleic acid. By RT-PCR using genotype specific primers, both the isolates RV-36 and RV-38 formed amplicons compatible with G10 and P[11] genotypes of RVA. RVA nucleic acids segments were also visualized by poliacrilamide gel electrophoresis (PAGE) method. The phylogenetic tree constructed according to the VP6 gene region showed that these isolates were in the Rotavirus A group and in the I2 cluster same as other bovine and some human RVA isolates. CONCLUSION: Succesful isolation of RVA G10P[11] was echieved in the cattle farm. As rotaviruses play the most important role in the etiology of diarrhea in newborn calves respected genotype G10P[11] should be considered in selection of the vaccines applied to the dams. Those isolates can be further evaluated as vaccine candidate.

Recent strains of influenza D virus create a new genetic cluster for European strains.

Bovine respiratory diseases (BRD) are one of the significant health problems for cattle breeding industry. Influenza D virus (IDV) alone or in combination with other respiratory pathogens plays a role in BRD. According to the IDV-HEF gene region, phylogenetic analyzes revealed five lineages: D/OK, D/660, D/Yama2016, D/Yama2019, and D/CA2019, so far. In this study, despite no success in virus isolation, the presence of IDV was investigated by RT-PCR (partial HEF gene region) in 219 nasal swab samples collected from cattle with BRD between 2012 and 2021. The presence of IDV was demonstrated in two samples, and genome characterization data of the IDV sequences both in the partial and complete HEF gene regions showed that one of the obtained sequences (D/bovine/Turkey-Bursa/ET-138/2021) was in the lineage D/Yama2019 while the other (D/bovine/Turkey-Bursa/ET-130/2013) created a new lineage tentatively called D/Bursa2013 as including few partial IDV sequences reported in Europe. Two nucleotide substitutions (nt252A→G, nt299T→C) were typically characterized for the tentative lineage D/Bursa2013, one of which also leads to a unique amino acid change at position aa100 (V→A). When the amino acid differences between the lineages were evaluated, amino acid substitution changes were detected in four regions [aa12 (Alanine→Aspartic acid), aa19 (Glycine→Arginine), aa22 (Proline→Serine), and aa110 (Aspargine→Arginine)] of the D/Yama2019 lineage, unlike the other lineages. Considering the most common D/OK lineage in Europe, many nucleotide substitutions were shown between D/OK and D/Bursa2013. Accordingly, aminoacid substitutions were observed in aa27 (Threonine→Asparagine) and aa100 (Valine→Alanine) in the D/bovine/Turkey-Bursa/ET-138/2021 sequence. Study results describe the circulation of D/Yama2019 and D/Bursa2013 (new lineage) in Turkey. Expansion of new strains seems possible due to the high mutation rate of influenza viruses. It is important to understand the development of IDV with comprehensive characterization studies.

Inhibition of bovine and ovine capripoxviruses (Lumpy skin disease virus and Sheeppox virus) by ivermectin occurs at different stages of propagation in vitro.

Capripoxvirus diseases are listed as reportable diseases by World Organization for Animal Health (OIE). Lumpy skin disease virus (LSDV) and sheeppox virus (SPPV), which can only be distinguished by molecular analysis, cause moderately, severe, or sometimes fatal infections in cattle and sheep. Even though vaccines are the most effective way to control the infection, their effectiveness may decrease in some cases. Therefore, it is significant to explore antiviral drugs against these diseases along with the vaccine. This study aimed to investigate the antiviral efficiency of ivermectin (IVM) at different stages of in vitro replication of LSDV and SPPV. For this purpose, viral titers (TCID50/mL) of the viruses not treated with IVM (0.0 µM) and treated with non-cytotoxic concentrations of IVM (1.0 and 2.5 µM) were compared during a nine-day (216 h) post-infection period by viral titration assay. At 2.5 µM concentrations of IVM, the mean viral titer was significantly (P<0.05) reduced by approximately three logs for the replication stage of LSDV and SPPV. To evaluate the antiviral activity of IVM against LSDV and SPPV by treatment at the virus attachment and penetration stages, the titers of the virus either untreated or treated with 2,5 µM IVM were compared by virus titration assay. The number of infectious virions for LSDV and SPPV were decreased by 99.82% and 99.87% at the viral replication stage, 68.38% and 25.01% at the attachment stage, and 57.83% and 0.0% at the penetration stage, respectively. It was determined that ivermectin is statistically more effective on LSDV than SPPV at the virus attachment and penetration stages (P<0.05). This study found that the drug IVM can inhibit capripoxviruses, including LSDV and SPPV at various stages of the propagation. Moreover, this research predicted the in vitro antiviral ability of IVM against capripoxvirus infections for the first time.

First isolation and molecular characterization of pseudorabies virus detected in Turkey.

BACKGROUND: Pigs are the main host species for the pseudorabies virus. It causes fatal encephalitis in many species, including humans. This article aims to report the first clinical case of pseudorabies as well as isolation and molecular characterization of the virus from a hunting dog in Bursa province, Turkey. METHODS AND RESULTS: The dog shows clinical signs including pruritus and neurological signs such as stumbling and inability to stand up compatible with pseudorabies. The virus isolates were obtained from the supernatant of fresh tissue samples from the cerebellum, cornu ammonis, spleen, salivary gland, conjunctival swab, serum, and PBMC samples. The glycoprotein C region is targeted for viral DNA amplification. Pseudorabies virus genome detected both in fresh tissues and supernatants of third passage on Vero cells. The number of PCR positive samples was dramatically increased after cell culture inoculations. Genome sequencing of strain Bursa-10303, which was isolated from a non-endemic area, identified it to belong to clade A. CONCLUSIONS: This study confirms the possible presence of pseudorabies infection in the wildlife reservoirs in Turkey. Future studies may clarify the importance of the infection in Turkey region, where there is no prevalent pig production.

In vitro antiviral activity of Thymbra spicata L. extract on bovine respiratory viruses (BCoV, BPIV-3, BRSV, BVDV and BoHV-1).

AIMS: Viral pathogens are the primary agents in bovine respiratory disease cases, and there is no direct effective antiviral drug application. Thymbra is a genus of oregano commonly found in Turkey. The primary component (34.9%) of the extract obtained from Thymbra spicata L. is the carvacrol which is used in traditional medicine. This study evaluates the potential antiviral activity and inactivation efficiency of T. spicata L. extract against bovine respiratory viruses, including BCoV, BPIV-3, BRSV, BVDV and BoHV-1. METHODS AND RESULTS: To evaluate its effect on viral replication, viral titres were taken from infected cells treated with non-cytotoxic T. spicata L. extract concentrations (0.75% and 1.5%, 1.32 and 2.64 µg/ml of carvacrol as active ingredient, respectively) and compared to non-treated infected cells. The viruses were treated directly with 1.5% T. spicata L. extract, and the viral titres were evaluated at certain time points to determine the efficiency of direct inactivation. The number of infectious virions for BCoV, BPIV-3, BRSV, BVDV and BoHV-1 treated with 1.5% T. spicata L. extract were decreased by 99.44%, 100.0%, 94.38%, 99.97% and 99.87%, respectively.T. spicata L. extract strongly inhibits the replication of mentioned viruses in a dose-dependent manner in vitro. In addition, T. spicata L. extract shared direct inactivation efficiency on the mentioned viruses in a time-dependent manner. CONCLUSION: This study shows the antiviral efficiency of T. spicata L. on BRD-related viral agents for the first time. The oregano species T. spicata and its main component, carvacrol, may have a potential for antiviral activity in the alternative treatment of respiratory viral diseases in cattle. SIGNIFICANCE AND IMPACT OF THE STUDY: Given the similarity of replication strategies, obtained data suggest the possible efficiency of T. spicata L. on human respiratory viruses.

Ivermectin also inhibits the replication of bovine respiratory viruses (BRSV, BPIV-3, BoHV-1, BCoV and BVDV) in vitro.

Bovine respiratory disease (BRD) complex is an important viral infection that causes huge economic losses in cattle herds worldwide. However, there is no directly effective antiviral drug application against respiratory viral pathogens; generally, the metaphylactic antibacterial drug applications are used for BRD. Ivermectin (IVM) is currently used as a broad-spectrum anti-parasitic agent both for veterinary and human medicine on some occasions. Moreover, since it is identified as an inhibitor for importin α/ß-mediated nuclear localization signal (NLS), IVM is also reported to have antiviral potential against several RNA and DNA viruses. Since therapeutic use of IVM in COVID-19 cases has recently been postulated, the potential antiviral activity of IVM against bovine respiratory viruses including BRSV, BPIV-3, BoHV-1, BCoV and BVDV are evaluated in this study. For these purposes, virus titration assay was used to evaluate titers in viral harvest from infected cells treated with non-cytotoxic IVM concentrations (1, 2.5 and 5 µM) and compared to titers from non-treated infected cells. This study indicated that IVM inhibits the replication of BCoV, BVDV, BRSV, BPIV-3 and BoHV-1 in a dose-dependent manner in vitro as well as number of extracellular infectious virions. In addition, it was demonstrated that IVM has no clear effect on the attachment and penetration steps of the replication of the studied viruses. Finally, this study shows for the first time that IVM can inhibit infection of BRD-related viral agents namely BCoV, BPIV-3, BVDV, BRSV and BoHV-1 at the concentrations of 2.5 and 5 µM. Consequently, IVM, which is licensed for antiparasitic indications, also deserves to be evaluated as a broad-spectrum antiviral in BRD cases caused by viral pathogens.

Molecular characterization and comparison of diagnostic methods for bovine respiratory viruses (BPIV-3, BRSV, BVDV, and BoHV-1) in field samples in northwestern Turkey.

The aim of this study was to evaluate the compatibility among virus isolation (VI), ELISA, and PCR for diagnosis of the major viral agents (BPIV-3, BRSV, BVDV, and BoHV-1) responsible for BRD in the field samples. For that purpose, a total of 193 samples (133 nasal swabs and 60 lung tissue samples) from cattle with respiratory signs in northwestern Turkey were examined. For VI, all the samples were inoculated at least 3 blind passages onto MDBK cell culture. In addition, the samples were tested by hemadsorption assay and RT-PCR for BPIV-3; nested RT-PCR for BRSV; immunoperoxidase monolayer assay, antigen-ELISA, and RT-PCR for BVDV; and antigen-ELISA and PCR for BoHV-1. The detected 1 (0.52%) BPIV-3 isolate was found to be in the genotype BPIV-3c. No BRSV isolate could be obtained, while 5 (2.59%) samples were evaluated positive in nested-RT PCR. The presence of BVDV antigen in 10 (5.18%) samples and the BVDV genome in 5 (2.59%) samples were detected, while non-cytopathogenic BVDV isolates were obtained only in 2 (1.04%) samples. The detected BVDV strains fell into the genetic clusters of BVDV-1a, -1f, and -1l. For detection of BoHV-1, although viral isolation and Ag-ELISA results were negative, presence of BoHV-1.1 genome was detected in 2 (1.04%) samples. By the results of VI, ELISA, and PCRs, 10.88% (21/193) of samples were found positive for the evaluated viruses. Depending on the obtained data, combined uses of the diagnostic methods were evaluated to be more reliable for routine diagnosis of bovine respiratory viruses.

Failure in dry period vaccination strategy for bovine viral diarrhea virus.

Bovine viral diarrhea is a common disease of cattle and has significant impact on animal welfare worldwide. There are fundamental approaches i.e. elimination of persistently infected animals, vaccination and biosecurity measures for effective control and eradication of BVD virus (BVDV). By this study, the presence of persistent infection with divergent BVDV subgenotype in the calves in a dairy herd having regular vaccination program was investigated. In the herd, vaccinated with a killed whole virion trivalent vaccine (composed of BVDV-1a) during the dry period of the cows, abortion cases were existed in the late autumn 2019. During herd screening by BVDV antigen-ELISA, 2 out of 300 dams were detected positive. Following, by ear notch-based BVDV antigen-ELISA, 30 calves were detected positive. Confirmation of persistent BVDV infection was performed 3 weeks later by testing with antigen-ELISA, where 8 of 9 selected newborn calves were positive for the second time. The entire antigen-ELISA positive samples were subjected to virus isolation on MDBK cell culture and identified as non-cytopathogenic pestiviruses by indirect immunoperoxidase assay. Presence of pestivirus RNA was detected in the 8 isolates by panpestivirus RT-PCR. Analysis of the 5'UTR regions revealed that BVDV-1 r circulate in the herd. Results of this study lead to questioning the efficiency of dry period vaccination strategy against BVDV. But otherwise, vaccination with BVDV-1a can be inefficient for complete protection against BVDV-1 r. Therefore, serological relationship between mentioned subgenotypes or protection by current vaccines against latest field isolates needs to be investigated before development of new BVDV vaccine candidates.

Persistent BVD virus infections in offspring from imported heifers.

The aim of this study was to investigate the possible risk of bovine viral diarrhea virus transport from imported live animals. For this purpose, two different groups of animals were sampled in this study. Group 1 consisted of pregnant heifers; group 2 consisted of male beef cattle imported during 2011-2012 and 2015, respectively. Blood samples were tested for pestivirus antigen using a commercial BVDV antigen ELISA. All the pregnant heifers were negative, but 9 out of 412 offspring and 5 of the 332 male cattle were BVDV antigen positive. Virus isolation and also investigation by RT-PCR were carried out by using 14 ELISA-positive samples. At the end of three blind passages, eight non-cytopathogenic isolates were obtained by indirect immunoperoxidase monolayer assay, which were also RT-PCR positive using panpesti-virus primers. After discriminative RT-PCR, all the isolates that were identified as BVDV-1 and 5'UTR-based analysis demonstrated the existence of BVDV-1b (n = 4), BVDV-1f (n = 2), BVDV-1 l (n = 1), and BVDV-1r (n = 1) subgenotypes. There was no BVDV subgroup that is newly introduced into the country. However, detection of persistent infection in calves born from imported animals demonstrates the risk of BVDV virus introduction by imported animals into the receiving country. Viral strains from persistently infected animals were characterized as BVDV-1b, which is predominant subgroup in the country where animals are imported. These results highlight a possible problem for the areas where a BVDV control program is currently ongoing. Additionally, sequences obtained in this study also showed that there are two distinct branches identified in BVDV-1l.

Presence of bovine hepacivirus in Turkish cattle.

Hepatitis C virus (HCV), a worldwide distributed human pathogen, causes one of the most important viral infections in human being. HCV is the type species of the genus Hepacivirus (Flaviviridae) in which recently discovered animal viruses i.e. from horses, bats, rodents and cattle are allocated. After preliminary reports in 2015 from German and African cattle, a wide distribution of bovine hepacivirus (BovHepV, Hepacivirus N) was proposed. We investigated the possible presence of BovHepV in serum samples from cattle in different locations of Turkey. Analyzing a total of 120 samples from 98 female (dairy) and 22 male (beef) cattle by real-time RT-PCR resulted in 15 (12.5%) positives. BovHepV infection was detected in 6 out of 10 locations included in the study. There were positive samples both from eastern and western parts of the country indicating possible wide distribution in the Turkish cattle population. Phylogenetic analysis of 9 selected positive samples clearly assigned 8 sequences to a separate cluster on the basis of NS3 gene region, while one of the sequences obtained from an imported animal from north of Italy grouped with sequences obtained from cattle in Germany. The latter finding may indicate possible occurrence of this genetic group of BovHepV not only in Germany but in other European countries. Results of the present study demonstrate the presence of BovHepV infections in Turkey and in The Middle East region.

Who's who in the Bovine viral diarrhea virus type 1 species: Genotypes L and R.

The bovine viral diarrhea virus type 1 species is responsible for cosmopolitan diseases affecting cattle and other ruminants, with relevant impact on animal production. The species presents high genomic heterogeneity, with implications on control and prophylactic programs. Genomic traits of different genetic groups are often related to geographic origin. Atypical sequences have been reported from Pestivirus isolates originated from cattle in Turkey. Based on phylogenetic analysis of 5' untranslated region and Npro and secondary structure analysis of the 5'-UTR RNA, Turkish isolates have been segregated in two distinct genotypes. Out of the twenty-three identified BVDV-1 genotypes, the Turkish clusters, named L and R or 1.16 and 1.14, according to palindromic nucleotide substitution genotyping method, represent genomic clusters so far, not described elsewhere, suggesting geographic segregation. In order to avoid confusion in the current taxonomy of the species, nomenclature of described homonymous genotypes, referred to different genomic clusters, should be corrected.

Variability and Global Distribution of Subgenotypes of Bovine Viral Diarrhea Virus.

Bovine viral diarrhea virus (BVDV) is a globally-distributed agent responsible for numerous clinical syndromes that lead to major economic losses. Two species, BVDV-1 and BVDV-2, discriminated on the basis of genetic and antigenic differences, are classified in the genus Pestivirus within the Flaviviridae family and distributed on all of the continents. BVDV-1 can be segregated into at least twenty-one subgenotypes (1a-1u), while four subgenotypes have been described for BVDV-2 (2a-2d). With respect to published sequences, the number of virus isolates described for BVDV-1 (88.2%) is considerably higher than for BVDV-2 (11.8%). The most frequently-reported BVDV-1 subgenotype are 1b, followed by 1a and 1c. The highest number of various BVDV subgenotypes has been documented in European countries, indicating greater genetic diversity of the virus on this continent. Current segregation of BVDV field isolates and the designation of subgenotypes are not harmonized. While the species BVDV-1 and BVDV-2 can be clearly differentiated independently from the portion of the genome being compared, analysis of different genomic regions can result in inconsistent assignment of some BVDV isolates to defined subgenotypes. To avoid non-conformities the authors recommend the development of a harmonized system for subdivision of BVDV isolates into defined subgenotypes.

The role of herpesviruses (BoHV-1 and BoHV-4) and pestiviruses (BVDV and BDV) in ruminant abortion cases in western Turkey.

The economic impact of abortions in ruminant breeders is one of the biggest problems in livestock. Of the infectious agents, viruses, especially herpesviruses and pestiviruses, are the most important causative agents of abortion in ruminants. In the present study, the role of herpesviruses (bovine herpesvirus-1 (BoHV-1), bovine herpesvirus-4 (BoHV-4)) and pestiviruses (bovine viral diarrhea virus (BVDV), border disease virus (BDV)) was investigated in cases of ruminant abortion between 2007 and 2015 in western Turkey. Out of 81 aborted fetal samples (60 calves, 19 lambs, and 2 kids), 42 were positive, which included 31 calves, 9 lambs, and 2 goats; 39 aborted fetal samples were negative for the pestivirus antigen ELISA. BoHV-1 antigen ELISA was positive in 3 cases which included 2 calves and 1 lamb; the remainder 78 cases were negative. Pestivirus and BoHV-1 were positive in 51.85 and 3.70 %, respectively, of the samples. According to PCR analysis, BoHV-4 was not encountered in any of the tested samples. In one of the calf fetus samples, both BVDV and BoHV-1 were positive; in one of the lamb fetus samples, BoHV-1 was positive. There was a much higher level of pestivirus antigen than the other viral agents evaluated in the study (p < 0.0001). The results of this study indicate that pestiviruses are a common viral cause of ruminant abortions in the examined area.

Serological detection of infection dynamics for respiratory viruses among dairy calves.

The aim of this study is to reveal infection dynamics of bovine respiratory syncytial virus (BRSV), bovine parainfluenza virus type 3 (PI-3), bovine herpesvirus 1 (BHV-1), bovine viral diarrhea virus (BVDV), bovine adenovirus type 3 (BAV-3) and bovine coronavirus (BCoV), which are important viral pathogens of respiratory disease complex in ruminants. Through such an analysis, the regression period of maternally derived antibodies and optimum vaccination time in calves can be recommended. A total of 10 farms were grouped as large (4)-, medium (2)- and small (4)- sized enterprises according to their animal population. Newborn calves (n: 94) delivered during a calendar month on the farms were studied. Blood samples were collected from these calves during their 1st, 2nd, 3rd, 4th, 6th, 8th, 10th and 12th months of age. Blood samples were also taken from their dams during the first sampling. Neutralizing antibody titers were detected using the serum neutralization test (SN50). New PI-3 and BVDV infections at the early stages of life were determined in the calves. Maternal antibodies began to decrease in the 2nd month for BRSV, BHV-1 and BAV-3 (97.8%, 25.5% and 91.4%) and in the 3rd month for PI-3, BVDV and BCoV (85.1%, 67% and 93.6%). It was concluded that maternal antibodies begin to decrease after the 1st month and that the possible first exposure of calves to respiratory viruses is after the 2nd month. Therefore, it is recommended that the first vaccination program including prime and booster doses can be applied between 2 and 4 months of age. Furthermore, re-vaccination of animals at 6 months after the booster dose is also suggested.

Serological relationships among subgroups in bovine viral diarrhea virus genotype 1 (BVDV-1).

Bovine viral diarrhea virus (BVDV) has various economic impacts associated with diarrhea, poor performance, an increase in the frequency of other infections and lethal outcomes. Both genotypes, namely BVDV-1 and BVDV-2, as well as different subgroups within these genotypes have been reported worldwide. Understanding the serological differences among the BVDV subgroups is important for disease epidemiology and prevention as well as vaccination programs. The aim of this study was to determine the serological relatedness among the subgroups in BVDV-1. For that purpose, sheep hyperimmune sera were collected against representative strains from 6 of the subgroups of BVDV-1 (BVDV-1a, -1b, -1d, -1f, -1h and -1l). The serum samples that gave the peak antibody titer to the homologous strains were used to perform cross neutralization assays. The highest homologous antibody titer (1:5160) was obtained against BVDV-1h. Regarding the cross neutralizing (heterologous) antibodies, the lowest titer (1:20) was produced by the BVDV-1f antiserum against the BVDV-1a and BVDV1-b viruses. The highest cross neutralizing titer (1:2580) achieved by the BVDV-1h antiserum was against the BVDV-1b strain. The cross neutralization results indicated particular serological differences between the recently described subgroup (BVDV-1l) and BVDV-1a/-1b, which are widely used in commercial vaccines. Considering the cross neutralization titers, it is concluded that selected BVDV-1l and BVDV-1h strains can be used for the development of diagnostic and control tools.

Characterisation of bovine viral diarrhoea virus (BVDV) isolates from an outbreak with haemorrhagic enteritis and severe pneumonia.

During 2007 a disease outbreak occurred in cattle in the Marmara region of western Turkey characterised by severe pneumonia and haemorrhagic enteritis in calves. Cases from three farms at different locations were examined and bovine viral diarrhoea virus (BVDV) isolated in all cases. Phylogenetic characterisation of the virus isolates allocated them in a new cluster tentatively named as BVDV-1r.

Tick survey and detection of Crimean-Congo hemorrhagic fever virus in tick species from a non-endemic area, South Marmara region, Turkey.

Crimean-Congo hemorrhagic fever (CCHF) is an increasing health concern in Turkey since 2002. There were also some recent human cases from the South Marmara region of Turkey; thus, a tick survey was performed, and possible vector tick species for the CCHF virus were determined in the region. A total of 740 adult ticks were collected from infested livestock from five locations: Çanakkale-Biga, Bursa-Orhaneli, Bursa-Keles, Balikesir and Bilecik. Total of 11 tick species from the genera Hyalomma, Rhipicephalus, Dermacentor, Ixodes and Haemaphysalis were identified. Rhipicephalus ticks were dominant in the region; the most frequently observed tick species was R. turanicus, (53.1 %), and only 15.4 % of the identified ticks were H. marginatum. The occurrence of H. rufipes infestation in the region fort he first time. A total of 73 pools of adult ticks were tested with both an antigen-detecting ELISA and RT real-time PCR (RT rt PCR). The presence of the CCHF virus was demonstrated in 9 (12.3 %) of the tested tick pools. Although seven of the tick pools were positive for the CCHF virus with both of the methods, one pool was positive only with RT rt PCR and the other pool was only positive with the ELISA. Positive results were obtained from ticks collected from cattle, sheep and goats from two locations, Bursa-Orhaneli and Bilecik. The CCHF virus was detected in R. turanicus (n = 3), R. bursa (n = 2), H. marginatum (n = 2) and D. marginatus (n = 2) ticks. The results of this study confirm the presence of the CCHF virus and present preliminary data on the vector tick species in the southern Marmara region of Turkey.

Serological evidence for infections with Borna disease virus in Turkey.

Distribution of Borna disease virus (BDV) infection outside endemic areas has been studied in several countries. We examined serum samples for anti-BDV antibodies in purebred racing horses and other domestic animals in Turkey. In total serum samples of 437 animals including 282 horses, 50 sheep, 25 goats, 50 cattle, and 30 cats were tested by indirect immunofluorescence assay (IFA). Anti-BDV antibodies were detected in 4.9% of horses, 12% of sheep, 4% of goats, 14% of cattle and 6.6% of cats. No statistical difference was observed between seroprevalence in Arabic and English purebred horses from four different racing centers (p > 0.05). Antibody titers ranged between 1:10 and 1:320. The highest antibody titers were found in sheep and horses and the lowest titer in cattle. Clinical symptoms of Borna disease were not observed in any animal of any species examined. This study confirms the presence of anti-BDV antibodies in racing horses as well as cat population in Turkey. Moreover anti-BDV antibodies are demonstrated for the first time in sheep, goats and cattle in Turkey.

Seroprevalence of canine herpesvirus-1 in Turkish dog population.

Canine herpesvirus-1 (CHV-1) is the agent of reproductive and respiratory disorders in adult dogs, and the infection generally results in haemorrhagic disease conditions and neonatal death. In this study, virus neutralisation test that used complement (VNT) as well as in-house ELISA were utilised to investigate the CHV-1 seroprevalence in the Turkish dog population. Among the 560 serum samples, 39.3% of the samples tested by ELISA were CHV-1 positive while 29.4% of the samples tested by VNT were CHV-1 positive. Compared to the individual dogs (39.0%), there was a higher CHV-1 seroprevalence (62.1%) found in the colony dogs (62.1%) (p=0.0002). However, there was an insignificant difference between male and female dogs. Although the highest antibody prevalence (56.7%) was found in Golden Retrievers, there were no significant variations detected among the dog breeds used in this study. Neutralizing antibody titres were very low (⩽1:16) in a high portion of the tested animals, confirming the rapid decrease of CHV-1 antibodies after the course of infection. The results of this study show that CHV-1 seroprevalence is moderately high in the Turkish dog population.