Atypical porcine pestivirus (APPV) was recently reported to be associated with neurologic disorders in newborn piglets. Investigations of 1,460 serum samples of apparently healthy pigs from different parts of Europe and Asia demonstrate a geographically wide distribution of genetically highly variable APPV and high APPV genome and antibody detection rates.

Background In the presented study we investigated the development of the humoral immune response against LSDV during the process of re-vaccination of cattle over a time span of 5 months. In addition, the performance of different serological techniques for antibody detection against LSDV was compared. For sample collection, an area without previous LSD outbreak reports in Serbia was selected. Seventy-nine cattle from twenty farms vaccinated in 2016 and re-vaccinated in 2017 were included in the study. Two farms from the same area with good calving management were selected for investigation of passive LSDV antibody transfer from vaccinated mothers to new-borne calves. Results All investigated cattle were healthy on the day of vaccination and during the whole study. Swelling at the injection site or other side effects of vaccination did not occur after re-vaccination in the study. Detection of LSD-specific antibodies was performed with the standard serological methods VNT and IFAT as well as a commercially available Capripox double antigen multi-species-ELISA. Capripoxvirus-specific antibodies were detected 46 to 47 weeks after vaccination in 2016, with VNT in 35.06% and with IFAT and ELISA in 33.77%. A secondary response was observed in all three tests 1 month after re-vaccination with a significant increase in seropositive animals compared to the results before re-vaccination. With all applied serological methods, the number of animals testing positive was significantly higher at 1 and 5 months post re-vaccination than before re-vaccination. No significant statistical difference ( p > 0.05) was observed between the results of all three tests used. The sensitivity and specificity of ELISA was estimated to be Se ELISA 91% and Sp ELISA 87% calculated by the results of VNT and Se ELISA 88% and Sp ELISA 76% calculated by the results of IFAT. Passive antibody transfer from vaccinated mothers to new-born calves was investigated at 14 days after birth. Discrepancies for the detection of LSDV specific antibodies between cows and newborn calves at the age of 14 days were observed in VNT and IFAT, but not in ELISA. Conclusion Of all tests used the commercially available ELISA shows to be the most useful for high throughput analysis compared to VNT or IFAT.

Until July 30th, 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.

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.

Porcine circovirus type 2 (PCV2) is the main causative agent of postweaning multisystemic wasting syndrome (PMWS). To characterize and determine the genetic diversity of PCV2 in the porcine population of Serbia, nucleotide and deduced amino acid sequences of the open reading frame 2 (ORF2) of PCV2 collected from the tissues of pigs that either had died as a result of PMWS or did not exhibit disease symptoms were analyzed. Sequencing and phylogenetic analysis showed considerable diversity among PCV2 ORF2 sequences and the existence of two main PCV2 genotypes, PCV2b and PCV2a, with at least three clusters, 1A/B, 1C and 2D. In order to provide further proof that the 1C strain is circulating in the porcine population, the whole viral genome of one PCV2 isolate was sequenced. Genotyping and phylogenetic analysis using the entire viral genome sequences confirmed that there was a PMWS-associated 1C strain emerging in Serbia. Our analysis also showed that PCV2b is dominant in the porcine population, and that it is exclusively associated with PMWS occurrences in the country. These data constitute a useful basis for further epidemiological studies regarding the heterogeneity of PCV2 strains on the European continent.