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Bluetongue (BT) is an emerging and re‐emerging communicable vector‐borne disease of animal health concern. A serosurvey was performed to assess exposure to BT virus (BTV) in zoo animals in Spain and to determine the dynamics of seropositivity in longitudinally sampled individuals during the study period. Serum samples were collected from 241 zoo animals belonging to 71 different species in five urban zoos (A‐E) in Spain between 2007 and 2019. Twenty‐four of these animals were longitudinally surveyed at three of the sampled zoos (zoos B, C and E) during the study period. Anti‐BTV antibodies were found in 46 (19.1%; 95% CI: 14.1–24.1) of the 241 captive animals analysed by commercial ELISA. A virus neutralization test confirmed specific antibodies against BTV‐1 and BTV‐4 in 25 (10.7%; 95% CI: 6.7–14.6) and five (3.0%; 95% CI: 0.3–4.0) animals, respectively. Two of the 24 longitudinally sampled individuals (one African elephant (Loxodanta africana) and one aoudad (Ammotragus lervia)) showed anti‐BTV antibodies at all samplings, whereas seroconversions were detected in one mouflon (Ovis aries musimon) in 2016, and one Asian elephant (Elephas maximus) in 2019. To the best of the authors' knowledge, this is the first large‐scale survey on BTV conducted in both artiodactyl and non‐artiodactyl zoo species worldwide. The results confirm BTV exposure in urban zoo parks in Spain, which could be of animal health and conservation concern. Circulation of BTV was detected in yearling animals in years when there were no reports of BTV outbreaks in livestock. Surveillance in artiodactyl and non‐artiodactyl zoo species could be a valuable tool for epidemiological monitoring of BTV. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate the duration of protective immunity against Porcine epidemic diarrhoea virus (PEDV). To do so, a two phases study was performed. In the first phase, 75 four-week-old pigs (group A) were orally inoculated (0 days post-inoculation; dpi) with a European PEDV G1b strain and 14 were kept as controls (group B). The second phase started five months later (154 dpi), when animals in group A were homologous challenged and animals in group B were challenged for first time. Clinical signs, viral shedding and immune responses were evaluated after each inoculation, including the determination of antibodies (ELISA and viral neutralization test, IgA and IgG ELISPOTs using peripheral blood mononuclear cells and lymph node cells) and the frequency of interferon-gamma (IFN-1) secreting cells. During the first phase, loose stools/liquid faeces were observed in all group A animals. Faecal shedding of PEDV occurred mostly during the first 14 days but, in some animals, persisted until 42 dpi. All inoculated animals seroconverted for specific-PEDV IgG and IgA, and for neutralizing antibodies (NA). At 154 dpi, 77% of pigs were still positive for NA. After that, the homologous challenge resulted in a booster for IgG, IgA, NA, as well as specific-PEDV IgG, IgA and IFN-1 secreting cells. In spite of that, PEDV was detected in faeces of all pigs from group A, indicating that the immune response did not prevent reinfection, although the duration of the viral shedding and the total load of virus shed were significantly lower for previously challenged pigs (p < .05). Taken together, the results indicated that, potentially, maintenance of PEDV infection within an endemic farm may occur by transmission to and from previously infected animals and also indicates that sterilizing immunity is shorter than the productive life of pigs. [ABSTRACT FROM AUTHOR]

Schmallenberg virus (SBV) is an emerging Culicoides‐borne Orthobunyavirus that affects ruminant species. Between 2011 and 2013, it was responsible for a large‐scale epidemic in Europe. In the present study, we aimed to determine the seroprevalence, spatial distribution and risk factors associated with SBV exposure in sheep and goats in the region where the first Schmallenberg disease outbreak in Spain was reported. Blood samples from 1,796 small ruminants from 120 farms were collected in Andalusia (southern Spain) between 2015 and 2017. Antibodies against SBV were detected in 536 of 1,796 animals (29.8%; 95%CI: 27.7–32.0) using a commercial blocking ELISA. The individual seroprevalence according to species was 31.1% (280/900; 95%CI: 28.1–34.1) in sheep and 28.6% (256/896; 95%CI: 25.6–31.5) in goats. The farm prevalence was 76.7% (95%CI: 69.1–84.2). Seropositivity to SBV was confirmed in both sheep and goats in all provinces by virus neutralization test. Two significant (p <.001) spatial clusters of high seroprevalence were identified. The generalized estimating equation analysis showed that management system (extensive), temperature (>14ºC) and altitude (<400 metres above sea level) were risk factors associated with SBV exposure in small ruminants. Our results highlight widespread but not homogeneous circulation of SBV in small ruminant populations in Spain. [ABSTRACT FROM AUTHOR]