Explore the vast range of titles available.

Lagoviruses are viruses of the Caliciviridae family affecting lagomorphs. Both pathogenic and non-pathogenic lagoviruses affect the European rabbit ( Oryctolagus cuniculus ), and they are phylogenetically distinguished. Rabbit Hemorrhagic Disease Virus (RHDV/GI.1) and Rabbit Hemorrhagic Disease Virus-2 (RHDV-2/GI.2) belong to the first group, while in the second group, several genotypes of Rabbit Calicivirus (RCV/GI.3-GI.4) are present. The first RCV strain was described in Italy in 1996, and since then, several RCV strains have been characterised in Europe and Australia. RCVs, different from the pathogenic hepatotropic RHDVs, have an enteric tropism and could be identified from the duodenum/intestine and faeces. This study aimed firstly to indirectly show through a seroepidemiological survey from 1998 to 2008 the circulation of RCVs strains in rabbit farms and then to genetically characterise RCV strains diagnosed in Italy in faecal and intestinal samples of wild and farmed rabbits collected in various regions in the following years (2000–2022). Of 262 analysed samples, 69 resulted in RT-PCR positive for lagovirus but negative for RHDV. Eleven RCV strains were characterised by complete vp60 sequencing. Phylogenetic analysis showed that the Italian RCV strains are grouped in European (RCV_E1/GI.3) and Australian (RCV_E2/GI.4) RCV clusters, with an estimated country prevalence of 26%. Based on the proposed genotype classification, considering the nucleotide differences of vp60 higher than 15%, we can hypothesise that two other genotypes, GI.5 and GI.6, might exist within the cluster of non-pathogenic viruses.

The Algerian government has recently supported plans to develop and increase commercial rabbit farming. A necessary condition for their success is to ensure rabbits’ health and protect farms from infectious diseases. Among these, Rabbit Haemorrhagic Disease (RHD) is one of the worst, causing high mortality and, thus, severe economic losses. Considering RHD’s high diffusibility, accurate surveillance systems and the proper and extensive use of vaccinal prevention are paramount in protecting rabbit populations. A sero-epidemiological survey on RHD was conducted in 19 herds located in different regions of Algeria to obtain a first overview of the monitoring system’s ability to detect RHD and estimate its presence and distribution in the country. The results showed that RHD is widespread in Algeria, far more than assumed based on the number of reported and diagnosed disease outbreaks. As in the rest of the world, RHDV2 was by far the prevalent, if not the only, agent of RHD in Algeria. By verifying the outcomes and results of using RHD vaccine in farms, it was shown the need to improve vaccination plans, likely through the strict application of the guidelines for RHD direct prophylaxis provided by the EU Lagmed project.

Porcine Reproductive and Respiratory Syndrome (PRRS) is a complex model of host/virus relationship. Disease control measures often includes \"acclimatization\", i.e. the exposure of PRRS-naïve gilts and sows to PRRSV-infected pigs and premises before the breeding period. In this respect, we had repeatedly observed an association between PRRSV-specific IgA responses in oral fluids (OF) of gilts and block of PRRSV spread. Therefore, we set out to investigate in vitro the inhibition of PRRSV replication by OF samples with different titers of PRRSV-specific IgA and IgG antibody, using Real-time RT PCR. PRRSV yield reduction in monocyte-derived macrophages was associated with the IgA content in OF samples, whereas the IgG-rich samples were sometimes associated with antibody-dependent enhancement (ADE) of replication. Accordingly, we could discriminate between ADE-positive and ADE-negative PRRSV strains. Next, we separated Ig isotypes in OF samples of PRRSV-infected pigs by means of protein A and size exclusion chromatography. The above results were confirmed by using separated Ig isotypes. Both dimeric and monomeric IgA were associated with the strongest reduction of PRRSV replication. The treatment of pig macrophages with separated OF antibodies before PRRSV infection was also associated with PRRSV yield reduction, along with clear changes of both CD163 and CD169 surface expression. Our results point at a role of mucosal IgA in the control of PRRSV replication by extra- and/or intracellular interaction with PRRSV, as well as by induction of signals leading to a reduced susceptibility of macrophages to PRRSV infection.

Neurofilament light chain (Nf-L) is a biomarker for axonal damage in human neurology but is understudied in cattle. With this study we wanted to determine Nf-L stability at two different storage temperatures and Nf-L levels in healthy cattle and the relationship with age, evaluate whether Nf-L holds diagnostic potential for neurological disorders, and whether an association exists between Nf-L in serum and in cerebrospinal fluid (CSF). To do this, we measured Nf-L levels in CSF and serum samples from 49 healthy and 75 sick cattle. Storage at −80 °C or −20 °C had no impact on Nf-L concentration. Physiological median Nf-L levels were 6.3 pg/mL (serum) and 414 pg/mL (CSF) in calves and 5.5 pg/mL (serum) and 828 pg/mL (CSF) in adult cattle. There was no association between Nf-L levels in CSF and calf age (r 2 0.07, p  = 0.13), while a weak association was found for Nf-L in serum (r 2 0.26, p  = 0.01), and a significant association in adult cattle (CSF, r 2 0.69, p  = 0.0001; serum, r 2 0.68, p  = 0.0003). CSF Nf-L levels were higher in samples from animals with degenerative (median Nf-L 49971 pg/mL) and infectious central nervous system (CNS) disorders (median Nf-L, age < 2 months 8863 pg/mL; age 2–12 months 17474 pg/mL; age 1–6 years 3546 pg/mL), CNS anomalies and metabolic/toxic disorders. There was a significant association between CSF Nf-L and serum Nf-L in cattle with neurological disorders (r 2 0.2, p  = 0.009). Taken together, these findings suggest the potential of Nf-L as a diagnostic tool in cattle neurology.

Background To date, whole genome sequencing has been performed mainly for isolates of Chlamydia trachomatis , C. pneumoniae , C. psittaci and C. abortus , but only a few isolates of C. pecorum have been entirely sequenced and this makes it difficult to understand its diversity and population structure. In this study the genome of two C. pecorum strains isolated from the lung of an Alpine chamois affected with pneumonia (isolate PV7855) and the brain of a water buffalo affected with meningoencephalomyelitis (isolate PV6959), were completely sequenced with MiSeq system (Illumina) and analyzed in their most polymorphic regions. Results The genome length and GC content of the two isolates were found to be consistent with other C. pecorum isolates and the gene content of polymorphic membrane proteins and plasticity zone was found to be very similar. Some differences were observed in the phospholipase genes for both isolates and in the number of genes in the plasticity zone, such as the presence of some hypothetical proteins in PV6959, not present in any other genomes analyzed in this study. Interestingly, PV6959 possesses an extra pmp and has an incomplete tryptophan biosynthesis operon. Plasmids were detected in both isolates. Conclusions Genome sequencing of the two C. pecorum strains did not reveal differences in length and GC content despite the origin from different animal species with different clinical disease. In the plasticity zone, the differences in the genes pattern might be related to the onset of specific symptoms or infection of specific hosts. The absence of a tryptophan biosynthesis pathway in PV6959 may suggest a strict relationship between C. pecorum and its host.

Background/Objectives: European Brown Hare Syndrome (EBHS) is an acute and highly contagious viral disease of hares that causes considerable economic losses on wild and captive-reared hares. No preventive treatments are currently available to defeat the disease. Immunoprophylactic and biosafety measures could be applied to prevent EBHS only in captive-reared hares, where vaccination is proposed as an effective strategy. Due to the lack of a cellular substrate for virus growth, commercially available vaccines are autovaccines produced from inactivated liver suspensions of hares dead for EBHS. Therefore, using a recombinant vaccine based on VP60 major capsid protein seems a viable alternative to overcome such a problem. Methods: the 6xHis C-terminal tagged VP60 protein of EBHSV was expressed and produced in baculovirus, purified by affinity chromatography and the self-assembled recombinant (rEVP60-His6) protein. To establish the protective properties of rEVP60-His6-based VLPs, hares were immunised with 50 and 100 µg of VLPs and parenterally challenged with EBHSV. Results: all hares vaccinated with 100 µg of VLPs survived after the experimental infection, demonstrating the excellent protective ability of this prototype VLPs-based vaccine. Conclusions: self-assembled EBHSV rEVP60-His6 protein was successfully produced following a rapid, simple, low-cost protocol. Although the protective efficacy of such VLPs were experimentally demonstrated, some key aspects remain to be clarified, including the duration of protection, the entity of the antibody response, and the ability to stimulate cell-mediated response. Last, an additional aspect to be evaluated is whether the use of an adjuvant can determine whether its presence improves the performance of the recombinant VLPs vaccine.

Transmissible spongiform encephalopathies (TSEs), or prion diseases, are mammalian neurodegenerative disorders characterized by a posttranslational conversion and brain accumulation of an insoluble, protease-resistant isoform ( PrPSc) of the host-encoded cellular prion protein ( PrPC). Human and animal TSE agents exist as different phenotypes that can be biochemically differentiated on the basis of the molecular mass of the protease-resistant PrPScfragments and the degree of glycosylation. Epidemiological, molecular, and transmission studies strongly suggest that the single strain of agent responsible for bovine spongiform encephalopathy (BSE) has infected humans, causing variant Creutzfeldt-Jakob disease. The unprecedented biological properties of the BSE agent, which circumvents the so-called \"species barrier\" between cattle and humans and adapts to different mammalian species, has raised considerable concern for human health. To date, it is unknown whether more than one strain might be responsible for cattle TSE or whether the BSE agent undergoes phenotypic variation after natural transmission. Here we provide evidence of a second cattle TSE. The disorder was pathologically characterized by the presence of PrP-immunopositive amyloid plaques, as opposed to the lack of amyloid deposition in typical BSE cases, and by a different pattern of regional distribution and topology of brain PrPScaccumulation. In addition, Western blot analysis showed a PrPSctype with predominance of the low molecular mass glycoform and a protease-resistant fragment of lower molecular mass than BSE- PrPSc. Strikingly, the molecular signature of this previously undescribed bovine PrPScwas similar to that encountered in a distinct subtype of sporadic Creutzfeldt-Jakob disease.

The European brown hare (Lepus europaeus) is a quite adaptable species, but populations have been decreasing for several decades in different countries, including Germany. To investigate infectious diseases as possible influences on observed population decline in the German federal state Schleswig-Holstein, 118 deceased free-ranging European brown hares were collected between 2017 and 2020 and underwent detailed postmortem examination with extended sampling. Infectious diseases were a major cause of death (34.7%). The number of juveniles found exceeded the adult ones. The main pathomorphological findings were hepatitis (32.8%), pneumonia (22.2%), nephritis (19.1%), liver necrosis (12.9%), and enteritis (40.7%). An unusual main finding was steatitis (20.9%) of unknown origin. Animals were mainly emaciated and showed high infection rates with Eimeria spp. (91.3%) and Trichostrongylus spp. (36.2%). European Brown Hare Syndrome Virus reached an epidemic status with few fatal infections (4.2%) and high seroprevalence (64.9%), whereas the prevalence of Rabbit Haemorrhagic Disease Virus 2 was very low (0.8%) in hares in Schleswig-Holstein. Pathogens such as Yersinia pseudotuberculosis (5.9%), Pasteurella multocida (0.8%), and Staphylococcus aureus (3.4%) only caused sporadic deaths. This study illustrates the wide distribution of various infectious pathogens with high mortality and even zoonotic potential. Infectious diseases need to be considered as an important influence on population dynamics in Schleswig-Holstein.

The calicivirus Rabbit haemorrhagic disease virus (RHDV) is widely used in Australia as a biocontrol agent to manage wild European rabbit (Oryctolagus cuniculus) populations. However, widespread herd immunity limits the effectiveness of the currently used strain, CAPM V-351. To overcome this, we developed an experimental platform for the selection and characterisation of novel RHDV strains. As RHDV does not replicate in cell culture, variant viruses were selected by serially passaging a highly virulent RHDV field isolate in immunologically naïve laboratory rabbits that were passively immunised 18-24 hours post-challenge with a neutralising monoclonal antibody. After seven passages, two amino acid substitutions in the P2 domain of the capsid protein became fixed within the virus population. Furthermore, a synonymous substitution within the coding sequence of the viral polymerase appeared and was also maintained in all subsequent passages. These findings demonstrate proof-of-concept that RHDV evolution can be experimentally manipulated to select for virus variants with altered phenotypes, in this case partial immune escape.