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Bluetongue (BT) causes an economic loss of $3 billion every year in the world. After two serious occurrences of BT (bluetongue virus [BTV] occurrence in 2006 and 2015), France has been controlling for decades, but it has not been eradicated. As the largest live cattle export market in the world, France is also one of the major exporters of breeding animals and genetic materials in the world. The biosafety of its exported cattle and products has always been a concern. The scenario tree quantitative model was used to analyze the risk of BTV release from French exported live cattle and bovine semen. The results showed that with the increase in vaccination coverage rates, the risk decreased. If the vaccine coverage is 0%, the areas with the highest average risk probability of BTV‐4 and BTV‐8 release from exported live cattle were Haute‐Savoie and Puy‐de‐Dôme, and the risk was 2.96 × 10–4 and 4.25 × 10–4, respectively. When the vaccine coverage was 90%, the risk probability of BTV‐4 and BTV‐8 release from exported live cattle was 2.96 × 10–5 and 4.24 × 10–5, respectively. The average probability of BTV‐8 release from bovine semen was 1.09 × 10–10. Sensitivity analysis showed that the probability of false negative polymerase chain reaction (PCR) test and the probability of BT infection in the bull breeding station had an impact on the model. The identification of high‐risk areas and the discovery of key control measures provide a reference for decision makers to assess the risk of French exports of live cattle and bovine semen. [ABSTRACT FROM AUTHOR]

Toxoplasmosis is a parasitic zoonosis caused by Toxoplasma gondii which infects warm‐blooded species worldwide. Humans can be infected through ingestion of tissue cysts from raw or undercooked meat, including game meat. A nationwide large‐scale cross‐sectional study was conducted to assess exposure to T. gondii in seven wild ruminant species in Spain. A total of 2,040 serum samples from 77 sampling sites randomly distributed in the five bioregions (BRs) covering mainland Spain were tested for antibodies against T. gondii using the modified agglutination test. The overall seroprevalence was 22.0% (449/2,040). Seroprevalence by species in decreasing order was as follows: 39.6% (141/356) in roe deer (Capreolus capreolus), 37.1% (138/372) in fallow deer (Dama dama), 16.6% (92/553) in red deer (Cervus elaphus), 14.0% (26/186) in Southern chamois (Rupicapra pyrenaica), 11.5% (24/209) in mouflon (Ovis aries musimon), 7.8% (27/346) in Iberian wild goat (Capra pyrenaica) and 5.6% (1/18) in Barbary sheep (Ammotragus lervia). Seropositivity was detected in 74.0% (57/77) of the sampling sites. Results indicate widespread but not homogeneous exposure to T. gondii in wild ruminant populations in Spain during the last two decades and highlight differences related to animal species and spatial distribution of these species in this country; this implies potential consequences of T. gondii for animal health, conservation and public health. [ABSTRACT FROM AUTHOR]

The objective of this systematic review and meta‐analysis was to summarize the available knowledge on the seroprevalence of T. gondii in roe deer (Capreolus capreolus) and red deer (Cervus elaphus) in Europe. A computerized literature search of electronic databases (PubMed and CAB abstracts) was performed along with hand searches of library resources for relevant papers, books, abstracts and conference proceedings. A random‐effect model was employed to calculate pooled seroprevalence estimates with 95% confidence intervals, and I2 statistic was used to assess heterogeneity. Further, moderator analysis was performed to evaluate the effect of geographical area on the seroprevalence in roe deer. From a total of 190 studies initially identified, 16 and 8 articles were included for roe deer and red deer, respectively. These comprise 3,913 roe deer and 2,913 red deer from different European countries. The pooled seroprevalence was estimated to be 29% (95% CI: 23%–35%) in roe deer and 15% (95% CI: 10%–20%) in red deer. High heterogeneity was detected in the seroprevalence data within each species. In roe deer, the pooled seroprevalence estimate was significantly different according to geographical area with 40% (95% CI: 31%–49%) in Western Europe, 31% (95% CI: 21%–43%) in Northern Europe, 27% (95% CI: 15%–41%) in Eastern Europe and 21% (95% CI: 14%–28%) in Southern Europe. The present study indicates a moderate exposure to T. gondii in roe deer and red deer in Europe, with very high prevalence in Western Europe. Our results highlight the significant risk associated to the consumption of venison, encouraging proper handling and cooking of game meat to prevent toxoplasmosis in humans. [ABSTRACT FROM AUTHOR]

Schmallenberg disease (SBD) is an emerging vector‐borne disease that affects domestic and wild ruminants. A long‐term serosurvey was conducted to assess exposure to Schmallenberg virus (SBV) in all the wild ruminant species present in mainland Spain. Between 2010 and 2016, sera from 1,216 animals were tested for antibodies against SBV using a commercial blocking ELISA. The overall prevalence of antibodies was 27.1% (95%CI: 24.7–29.7). Statistically significant differences among species were observed, with significantly higher seropositivity found in fallow deer (Dama dama) (45.6%; 99/217), red deer (Cervus elaphus) (31.6%; 97/307) and mouflon (Ovis aries musimon) (28.0%; 33/118) compared to Barbary sheep (Ammotragus lervia) (22.2%; 8/36), Iberian wild goat (Capra pyrenaica) (19.9%; 49/246), roe deer (Capreolus capreolus) (17.5%; 34/194) and Southern chamois (Rupicapra pyrenaica) (10.2%; 10/98). Seropositive animals were detected in 81.4% (57/70; 95%CI: 70.8–88.8) of the sampled populations. SBV seroprevalence ranged from 18.8% (48/256) in bioregion (BR)2 (north‐central, Mediterranean) to 32.3% (31/96) in BR1 (northeastern or Atlantic, Eurosiberian). Anti‐SBV antibodies were not found before 2012, when the first outbreak of SBD was reported in Spain. In contrast, seropositivity was detected uninterruptedly during the period 2012–2016 and anti‐SBV antibodies were found in yearling animals in each of these years. Our results provide evidence of widespread endemic circulation of SBV among wild ruminant populations in mainland Spain in recent years. Surveillance in these species could be a useful tool for monitoring SBV in Europe, particularly in areas where wild ruminants share habitats with livestock. [ABSTRACT FROM AUTHOR]

The current flapping wing adopts T-shaped or cross-shaped tail fin to adjust its flight posture. However, how the tail fin will affect the hover control is not very clear. So, the effects of the two types of tail on flight will be analyzed and compared by actual flight tests in this paper. Firstly, we proposed a new X-wing single-bar biplane flapping-wing mechanism with two pairs of wings. Thereafter, the overall structure, gearbox structure, tail, frame, and control system of the flapping wing were designed and analyzed. Secondly, the control mechanism of hover is analyzed to describe the effect of two-tail fin on posture control. Thirdly, the Beetle was used as the control unit to achieve a controllable flight of flapping wing. The MPU6050 electronic gyroscope was used to monitor the drone's posture in real time, and the Bluetooth BLE4.0 wireless communication module was used to receive remote control instructions. At last, to verify the flight effect, two actual flapping wings were fabricated and flight experiments were conducted. The experiments show that the cross-shaped tail fin has a better controllable performance than the T-shaped tail fin. The flapping wing has a high lift-to-mass ratio and good maneuverability. The designed control system can achieve the controllable flight of the flapping wing. [ABSTRACT FROM AUTHOR]

Tick‐borne encephalitis virus (TBEV) is the causative agent of tick‐borne encephalitis (TBE). TBEV is one of the most important neurological pathogens transmitted by tick bites in Europe. The objectives of this study were to investigate the seroprevalence of TBE antibodies in cervids in Norway and the possible emergence of new foci, and furthermore to evaluate if cervids can function as sentinel animals for the distribution of TBEV in the country. Serum samples from 286 moose, 148 roe deer, 140 red deer and 83 reindeer from all over Norway were collected and screened for TBE immunoglobulin G (IgG) antibodies with a modified commercial enzyme‐linked immunosorbent assay (ELISA) and confirmed by TBEV serum neutralisation test (SNT). The overall seroprevalence against the TBEV complex in the cervid specimens from Norway was 4.6%. The highest number of seropositive cervids was found in south‐eastern Norway, but seropositive cervids were also detected in southern‐ and central Norway. Antibodies against TBEV detected by SNT were present in 9.4% of the moose samples, 1.4% in red deer, 0.7% in roe deer, and nil in reindeer. The majority of the positive samples in our study originated from areas where human cases of TBE have been reported in Norway. The study is the first comprehensive screening of cervid species in Norway for antibodies to TBEV, and shows that cervids are useful sentinel animals to indicate TBEV occurrence, as supplement to studies in ticks. Furthermore, the results indicate that TBEV might be spreading northwards in Norway. This information may be of relevance for public health considerations and supports previous findings of TBEV in ticks in Norway. [ABSTRACT FROM AUTHOR]

Bluetongue virus serotype 8 (BTV‐8) caused an epizootic in Europe in 2006/09. Transplacental transmission of BTV‐8 was demonstrated leading to abortions, congenital malformations or nervous clinical signs in newborn calves. BTV‐8 re‐emerged in France in 2015. Although the re‐emergent strain is nearly genetically identical to the one that had circulated in 2006/2009, it has caused very few clinical cases. However, from mid‐December 2018 to April 2019, cases of calves with congenital malformations or displaying nervous clinical signs occurred in some departments (French administrative unit) in mainland France. Blood samples from these animals were sent to local laboratories, and the positive ones were confirmed at the French Bluetongue reference laboratory (BT‐NRL). Out of 580 samples found positive at the local laboratories, 544 were confirmed as RT‐PCR BTV‐8 positive. The 36 samples found positive in the local laboratories and negative in the BT‐NRL were all at the limit of RT‐PCR detection. Hundred eighty‐eight of the confirmed samples were also tested for the presence of Schmallenberg virus (SBV) and bovine virus diarrhoea virus (BVDV) infection: 4 were found positive for BVDV and none for SBV. The main clinical signs recorded for 244 calves, for which a reporting form was completed by veterinarians, included nervous clinical signs (81%), amaurosis (72%) and decrease/ no suckling reflex (40%). Hydranencephaly and microphthalmia were reported in 19 calves out of 27 in which a necropsy was practiced after death or euthanasia. These results indicate that the re‐emergent strain of BTV‐8 can cross the transplacental barrier and cause congenital malformations or nervous clinical signs in calves. [ABSTRACT FROM AUTHOR]

Transient receptor potential ankyrin 1 (TRPA1) is a sensor of nociceptive stimuli, expressed predominantly in a subpopulation of peptidergic sensory neurons which co-express the noxious heat-sensor transient receptor potential vanilloid 1. In this study, we describe a spinal cord synaptosome-calcitonin gene-related peptide (CGRP) release assay for examining activation of TRPA1 natively expressed on the central terminals of dorsal root ganglion neurons. We have shown for the first time that activation of TRPA1 channels expressed on spinal cord synaptosomes by a selection of agonists evokes a concentration-dependent release of CGRP which is inhibited by TRPA1 antagonists. In addition, our results demonstrate that depolarization of spinal cord synaptosomes by a high concentration of KCl induces CGRP release via a T-type calcium channeldependent mechanism whilst TRPA1-induced CGRP release functions independently of voltage-gated calcium channel activation. Finally, we have shown that pre-treatment of synaptosomes with the opioid agonist, morphine, results in a reduction of depolarization-induced CGRP release. This study has demonstrated the use of a dorsal spinal cord homogenate assay for investigation of natively expressed TRPA1 channels and for modulation of depolarizing stimuli at the level of the dorsal spinal cord. [ABSTRACT FROM AUTHOR]

On September 6, 2008, bluetongue was detected for the first time in Sweden. Intensified active surveillance in cattle and vector surveillance, prompted by the situation in northern Europe, preceded the detection. A vaccination campaign and intensive surveillance activities were initiated nationally, but with a focus on the southern part of the country. Measures included both active and passive surveillance by serology and PCR in ruminants, along with vector surveillance. The investigations revealed that the infection occurred over a large area of southern Sweden during September and October 2008, despite comparatively low vector activity, an apparently low viral load and no clinical disease. Transplacental infection was detected in one case. [ABSTRACT FROM AUTHOR]

Following the first ever case of bluetongue in Denmark during late 2007, further outbreaks were observed in Denmark during 2008, despite vaccination against bluetongue virus (BTV) serotype 8 (BTV-8) in the southern part of the country. In total, 15 separate outbreaks of infection were identified, mostly as a result of clinical suspicions but also because of surveillance of bulk milk samples. These outbreaks led to extensions of the original vaccination zone planned for 2008. Blood samples from clinical suspects were analysed using ELISA and real-time RT-PCR assays for the presence of anti-BTV antibodies and viral RNA, respectively. A newly infected calf from the primary outbreak in 2008 was studied for a period of three months, during which time it seroconverted to BTV, but the presence of viral RNA in its blood was maintained throughout this time. Each outbreak was caused by BTV-8, as determined by a serotype-specific real-time RT-PCR assay. Furthermore, the nucleotide sequence of a portion of segment 2 of the viral RNA (encoding the outer capsid protein VP2) from the samples analysed was identical to the BTV-8 segment 2 that circulated in the Netherlands during 2006. [ABSTRACT FROM AUTHOR]

The article discusses the study which shows the evidence of BTV-8 field strains to cross the placental barrier in sheep under experimental conditions. The study used three Dorset ewes in which each respondent is inoculated and administered intradermal injections. In addition, the study found low presence of antibody titres of the lamb after experimental BTV-8 infection in sheep with strain-dependent feature.