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Since the first introduction of African swine fever (ASF) into the European wild boar population in 1957, the question of virus survival in carcasses of animals that succumbed to the disease has been discussed. The causative African swine fever virus (ASFV) is known to be very stable in the environment. Thus, carcasses of infected wild boar could play a major role as ASFV reservoir and thereby help to locally maintain and spread the disease in wild boar populations. To minimize this risk, removal of wild boar carcasses in ASF affected areas is regarded to be crucial for effective disease control. If removal is not feasible, carcasses are usually disposed by burial on the spot to avoid direct contact of wild boar to the infection source. In this study, carcasses of ASFV infected wild boar buried in Lithuania at different time points and locations have been excavated and retested for the presence of infectious ASFV by in vitro assays and for viral genome by qPCR. Soil samples potentially contaminated by body fluids have been additionally tested for viral genome. In seventeen out of twenty burial sites, samples of excavated carcasses were positive for ASFV genome. However, in none of the carcass samples ASFV could be isolated. On seven sites soil samples contained ASF viral DNA. These results unexpectedly negate the long-term persistence of infectious ASFV in wild boar carcasses independent from the burial time. In this context, sensitivity of ASFV isolation from carcass samples versus susceptibility of animals and doses needed for oral inoculation has to be further investigated. Furthermore, research is required to consider alternative ASF infection sources and drivers in the infection cycle among wild boar.

African swine fever (ASF) is a contagious disease of key importance that occurs in wild boar population and domestic pigs. To date, there is no vaccine or treatment available, hence disease surveillance and stamping out in case of an outbreak is the only way to control it. A duplex ASF-IC real-time PCR assay was optimised using field samples obtained in Lithuania and results of singleplex and duplex real-time PCR assays allowing the identification of the ASF virus were compared. The specificity and sensitivity of ASF virus detection was validated using a reference sample of positive and negative virus nucleic acid and ASF virus positive and negative samples obtained from animals in Lithuania. Results prove that duplex ASF-IC real-time PCR assay provides a rapid, sensitive, and reliable molecular tool for ASF virus detection in wild boar population and domestic pigs. In general, it was found that duplex ASF-IC real-time PCR assay proves to be faster and more sensitive than singleplex real-time PCR and therefore has a high potential to be applied in routine analysis.

In January 2014 the first case of African swine fever (ASF) in wild boar of the Baltic States was reported from Lithuania. It has been the first occurrence of the disease in Eastern EU member states. Since then, the disease spread further affecting not only the Baltic States and Poland but also south-eastern Europe, the Czech Republic and Belgium. The spreading pattern of ASF with its long-distance spread of several hundreds of kilometers on the one hand and the endemic situation in wild boar on the other is far from being understood. By analyzing data of ASF cases in wild boar along with implemented control measures in Lithuania from 2014&ndash, 2018 this study aims to contribute to a better understanding of the disease. In brief, despite huge efforts to eradicate ASF, the disease is now endemic in the Lithuanian wild boar population. About 86% of Lithuanian&rsquo, s territory is affected and over 3225 ASF cases in wild boar have been notified since 2014. The ASF epidemic led to a considerable decline in wild boar hunting bags. Intensified hunting might have reduced the wild boar population but this effect cannot be differentiated from the population decline caused by the disease itself. However, for ASF detection sampling of wild boar found dead supported by financial incentives turned out to be one of the most effective tools.

A total of one hundred and fifty-three canine cutaneous tumors were examined and analyzed using the standard haematoxylin-eosin staining method. Additionally, tumors were examined immunohistochemically (41.4%) with antibodies LP34, AE1/AE3, V9 and histochemically (24.8%) with toluidine blue. Epithelial and melanocytic tumors of the skin accounted for 52.3% and mesenchymal tumours constituted 47.7%. All epidermal and follicular tumors demonstrated positive immunostaining for “LP34” antibodies. Fibromas and fibrosarcomas, which were immunohistochemically positive for antibodies “V9”, demonstrated negative immunostaining for antibodies “LP34”. As many as 47.4% of all round cell tumors showed positive staining with toluidine blue. Antibodies “LP34” are helpful for the differential diagnosis of epithelial cells of tumors in canine skin, skin adnexal and subcutaneous tissues. Antibodies “AE1/AE3” could be helpful for detecting metastatic glandular epithelial cells in the skin. Moreover, antibodies “V9” could be a useful tool to diagnose the cutaneous tumors consisting of fibrous tissue cells. Staining round cell tumors with toluidine blue may give valuable information on regarding mast cell tumors.

Group A pharmacologically active substances monitoring data in the Republic of Lithuania (LR) during the period 1999-2008 are presented. Peer review is based on data taken from residue monitoring plans of the years 1999-2008 and the National Food and Veterinary Risk Assessment Institute (NFVRAI) reports on analyses performed in various foods. The data were analysed with the SPSS statistical package, using descriptive statistics and generalised linear modelling methods. Retrospective analysis of residue monitoring results showed that food processed from animal products presented no risk to consumers as regards to substances of Group A1, A2, A3, A4 and A5. One substance of Group A6 (chloramphenicol) was detected in bovine milk in 2003 (9%), 2006 (2%) and 2008 (1.4%). The decreasing trend is confirmed by statistical data analyses, where year of monitoring (P ≤ 0.0001), product (P ≤ 0.1) and their interaction (P ≤ 0.0001) proved the positive effect of the monitoring system.

The objective of this study was to evaluate the molecular epidemiology of rabies virus G-gene partial sequences in rabies positive field samples, isolated in different regions of Lithuania, and to compare the sequences phylogenetically with various rabies virus isolates of wild carnivores from the Baltic Sea region, Europe and Russia. Twenty brain samples of rabid animals, collected during the period 2006-2011, were investigated. Multiple alignments of 358 nt G gene (nt 3324-3682) sequences were performed using ClustalW with default settings. Phylogenetic and molecular evolutionary analyses were conducted using the Neighbor-Joining method (NJ) in MEGA version 4. The phylogenetic investigations of rabies virus glycoprotein indicate that the Lithuanian rabies virus isolates’ G-sequences were closely related and showed 89.8-98.9 % of nt identity. The G-sequences between Lithuanian raccoon dog and red fox rabies virus isolates were more conservative (97.2 % nt identity) than the rabies virus isolates inside the raccoon dog group (95.1 % nt identity). Two Lithuanian raccoon dog rabies virus isolate G-sequences were rather divergent (90.8 and 91.2 % nt identity) and were closely associated with rabies virus isolate G-sequences from Estonia (92.5 % nt identity), Russia (91.0 %) and Poland (89.3 %) respectively. The comparative investigation of G-sequences between the Lithuanian rabies virus isolates and different isolates from Germany, Slovenia and France indicated 84.2 % nt identity, whereas the G-sequences of Lithuanian rabies virus isolates and rabies virus isolate G-sequences from Russia were 88.1 % nt identical., Svrha ovog rada bila je odrediti molekularnu epidemiologiju djelomičnih sekvencija gena G virusa bjesnoće u terenskim uzorcima pozitivnima na bjesnoću iz različitih područja Litve te ih filogenetski usporediti s različitim izolatima virusa bjesnoće iz divljih mesojeda na području Baltičkog jezera, Europe i Rusije. Pretraženo je 20 uzoraka tkiva mozga bijesnih životinja prikupljenih u razdoblju od 2006. do 2011. Višestruka poravnanja sekvencija od 358 nukleotida gena G (nt 3324-3682) učinjena su pomoću programa ClustalW. Filogenetska i molekularno evolucijska analiza provedena je metodom združivanja genetski najsličnijih sojeva (engl. Neighbour-joining method) u MEGA verziji 4. Filogenetska istraživanja glikoproteina virusa naznačuju da su G-sekvencije izolata litavskoga virusa bjesnoće usko srodne i pokazuju 89,8-98,9 % nt identičnosti. G-sekvencije izolata virusa bjesnoće iz litavskog rakunskog psa i crvenih lisica bile su sačuvanije (97,2 % nt identičnosti) nego izolati virusa bjesnoće izdvojeni iz rakunskog psa (95,1 % nt identičnosti). G-sekvencije dvaju izolata iz litavskih rakunskih pasa bile su prilično divergentne (90,8 i 91,2 % nt identičnosti) i usko srodne s G-sekvencijama izolata virusa bjesnoće iz Estonije (92,5 % nt identičnosti), Rusije (91,0 %) i Poljske (89,3 %). Komparativno istraživanje G-sekvencije litavskih izolata virusa bjesnoće i različitih izolata iz Njemačke, Slovenije i Francuske pokazalo je 84,2 % nt identičnosti, dok je identičnost između G-sekvencije između litavskih izolata virusa bjesnoće i ruskih izolata bila na razini 88,1 % nt identičnosti.

African swine fever virus (ASFV) was first reported in eastern Europe/Eurasia in 2007. Continued spread of ASFV has placed central European countries at risk, and in 2014, ASFV was detected in Lithuania and Poland. Sequencing showed the isolates are identical to a 2013 ASFV from Belarus but differ from ASFV isolated in Georgia in 2007.

Background Oral rabies vaccination (ORV) in rabies infected regions should target the primary rabies vector species, which in Lithuania includes raccoon dogs as well as red foxes. Specific investigations on ORV in raccoon dogs are needed e.g. evaluation of vaccine effectiveness under field conditions. The objective of the current study was to investigate the efficacy of the ORV programme 2006-2010 in Lithuania by examining the number of rabies cases and estimating the prevalences of a tetracycline biomarker (TTC) and rabies virus antibodies in raccoon dogs. Methods From 2006 to 2010, 12.5 million rabies vaccine-baits were distributed by aircraft. Baiting occurred twice per year (spring and autumn), targeting raccoon dogs and red foxes in a 63,000 km2 area of Lithuania. The mandibles of raccoon dogs found dead or killed in the vaccination area were analyzed by fluorescence microscopy for the presence of the TTC. Rabies virus sera neutralizing anti-glycoprotein antibody titres were determined using an indirect ELISA method and seroconversion (> 0.5 EU/ml) rates were estimated. Results During the study period, 51.5% of raccoon dog mandibles were positive for TTC. 1688 of 3260 tested adults and 69 of 175 tested cubs were TTC positive. Forty-seven percent of raccoon dog serum samples were positive for rabies virus antibodies. 302 of 621 investigated adults and 33 of 95 investigated cubs were seropositive. In the same time 302 of 684 and 43 of 124 tested samples were TTC and ELISA positive in spring; whereas 1455 of 2751 and 292 of 592 tested samples were TTC and ELISA positive in autumn. There was a positive correlation between the number of TTC and antibody positive animals for both adult and cub groups. Conclusions ORV was effective in reducing the prevalence of rabies in the raccoon dog population in Lithuania. The prevalence of rabies cases in raccoon dogs in Lithuania decreased from 60.7% in 2006-2007 to 6.5% in 2009-2010.

During the oral vaccination against rabies (ORV) in 2007–2010, phylogenetic analysis of rabies virus (RV) isolated from domestic and wild animals, was performed in the nucleoprotein (N) gene region. In total, 66 RV-positive brain samples were analysed: 52 samples from wild and 14 from domestic animals. The investigation was carried out at the National Food and Veterinary Risk Assessment Institute. For confirmation, RV identification in the analysed brain samples (n = 66) was performed by three methods: fluorescent antibody test (FAT), rabies tissue culture infection test (RTCIT) and reverse transcription polymerase chain reaction (RT-PCR). The results obtained by the three methods employed were similar: RV was identified in 66 samples of brain. The region of RT-PCR gene was amplified from (n = 66) positive brain samples and the obtained sequences of 362 bp nucleotides were compared with the selected other sequences of rabies virus from the GenBank. The phylogenetic analysis of N gene from wild and domestic animals showed a close genetic relationship between the different RV isolates irrespective of species or regional origin. The obtained results indicate that all RV strains in Lithuania belong to the first RV genotype of the North-East European group. Keywords: rabies virus, phylogenetic, wild, domestic

Molecular epidemiology has proven to be an essential tool in the control of classical swine fever (CSF) and its use has significantly increased during the past two decades. Phylogenetic analysis is a prerequisite for virus tracing and thus allows implementing more effective control measures. So far, fragments of the 5´NTR (150 nucleotides, nt) and the E2 gene (190 nt) have frequently been used for phylogenetic analyses. The short sequence lengths represent a limiting factor for differentiation of closely related isolates and also for confidence levels of proposed CSFV groups and subgroups. In this study, we used a set of 33 CSFV isolates in order to determine the nucleotide sequences of a 3508–3510 nt region within the 5´ terminal third of the viral genome. Including 22 additional sequences from GenBank database different regions of the genome, comprising the formerly used short 5´NTR and E2 fragments as well as the genomic regions encoding the individual viral proteins Npro, C, Erns, E1, and E2, were compared with respect to variability and suitability for phylogenetic analysis. Full-length E2 encoding sequences (1119 nt) proved to be most suitable for reliable and statistically significant phylogeny and analyses revealed results as good as obtained with the much longer entire 5´NTR-E2 sequences. This strategy is therefore recommended by the EU and OIE Reference Laboratory for CSF as it provides a solid and improved basis for CSFV molecular epidemiology. Finally, the power of this method is illustrated by the phylogenetic analysis of closely related CSFV isolates from a recent outbreak in Lithuania.