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Introduction: Neospora caninum is an important cause of abortion in cattle worldwide. Infection in cattle occurs horizontally by ingestion of oocysts shed by canids or vertically, from an infected dam to the fetus, and may result in abortion, stillbirth, or birth of seropositive offspring. The control of bovine neosporosis is difficult and costly. The objectives of this study were to estimate the current nationwide seroprevalence of N. caninum infections in Swiss cattle and to assess risk factors for infection with this parasite., Methods: We conducted a cross-sectional study with cattle farms randomly selected and stratified according to population size, resulting in a sample of 780 female cattle. The cattle originated from 161 farms distributed over all Switzerland. The serum samples were tested for antibodies against N. caninum using a commercial ELISA and if inconclusive, retested using an in-house immunoblot technique. To collect farm parameters relevant to N. caninum transmission and prevention, farm owners were mailed a questionnaire which addressed topics putatively related to N. caninum infection such as husbandry, history of abortion, and presence of dogs on farm. Univariate analysis by generalized linear mixed model (with animal seropositivity as outcome variable) and logistic regression modeling (with farm seropositivity as outcome variable) was conducted on farm parameters investigated in the questionnaire., Results: By ELISA and immunoblot, 4.2% (33/780) of cattle sera yielded positive results. At the farm level, 16.2% (26/161) of the sampled farms had at least one seropositive animal. The return rate of the valid questionnaires was 54.0%. At the animal level, odds for farm seropositivity were 3.8 times higher when rodents had been recorded by the farmer as a problem on the farm. At the farm-level, two protective factors were identified: rearing of replacement heifers and feeding of concentrated feed., Conclusion: We recorded a low seroprevalence of N. caninum in a random sample of Swiss cattle representative for the years 2017-2018. Based on a questionnaire survey, we could identify risk and protective factors for infection with N. caninum , however their biological relevance needs to be confirmed in further studies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Gliga, Basso, Ardüser, Moore-Jones, Schares, Zanolari and Frey.)

Toxoplasma gondii and Neospora caninum infections are important causes of abortion in ruminants. Besides, meat from T. gondii infected animals represent a major infection source for humans. The occurrence of these protozoan parasites in Switzerland was investigated both, in a nationwide cross-sectional serological survey, and by molecular methods in aborted sheep and goat foetuses. A total of 653 sheep from 143 farms and 748 goats from 164 farms were tested by commercial ELISAs and inconclusive results were defined by immunoblot. Besides, a risk factor analysis for seropositivity was performed. The observed seroprevalences for T. gondii in sheep and goats were 66.3% and 50.5% at the animal level, and 90.9% and 81.1% at the farm level, respectively. For N. caninum , the detected seroprevalences in sheep and goats were 0.8% and 0.9% at the animal level, and 2.8% and 1.8% at the farm level, respectively. Older small ruminants, and sheep (vs. goats) had a higher risk of being seropositive to T. gondii. Alpine grazing in summer was identified as a protective factor for seropositivity to T. gondii in both animal species. Toxoplasma gondii and N. caninum DNA were detected in 6.1% and 2.4% ( n  = 82), and in 6.8% and 1.4% ( n  = 73) of the tested ovine and caprine foetuses, respectively. These results suggest the involvement of these parasites in abortions and reveal a high prevalence of T. gondii and lower prevalence of N. caninum infections in small ruminants in Switzerland. They also suggest that consumption of undercooked meat from T. gondii infected sheep and goats may represent a risk for public health., Competing Interests: The authors declare that they have no competing interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Authors.)

In the early 1800s, the European roe deer ( Capreolus capreolus ) was probably extirpated from Switzerland, due to overhunting and deforestation. After a federal law was enacted in 1875 to protect lactating females and young, and limiting the hunting season, the roe deer successfully recovered and recolonized Switzerland. In this study, we use mitochondrial DNA and nuclear DNA markers to investigate the recolonization and assess contemporary genetic structure in relation to broad topographic features, in order to understand underlying ecological processes, inform future roe deer management strategies, and explore the opportunity for development of forensic traceability tools. The results concerning the recolonization origin support natural, multidirectional immigration from neighboring countries. We further demonstrate that there is evidence of weak genetic differentiation within Switzerland among topographic regions. Finally, we conclude that the genetic data support the recognition of a single roe deer management unit within Switzerland, within which there is a potential for broad-scale geographic origin assignment using nuclear markers to support law enforcement., Competing Interests: The authors declare no conflict of interest., (© 2022 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Footrot is a worldwide economically important, debilitating disease caused by Dichelobacter nodosus. In sheep (Ovis aries), it is characterized by lesions of varying severity, depending on the strain, whereas Alpine ibex (Capra ibex) seem to develop severe lesions, whatever the strain. Healthy carriers occur in livestock but are rare in wild ruminants. Using a triangulation approach (retrospective questionnaire survey, necropsy database screening, and pathogen prevalence estimation in selected ibex colonies with and without footrot), we aimed at evaluating the importance of footrot in the ibex population, identifying potential risk factors for disease occurrence in this species, and defining the epidemiological role of ibex. Our study revealed that footrot occurs throughout the entire ibex territory (34% of the Swiss ibex colonies affected) but only as a sporadic disease (mostly one case per disease event), although the situation differed among footrot-positive colonies because half of them had experienced outbreak recurrences. Risk factor analysis for the occurrence of footrot in ibex colonies suggested an absence of an effect of meteorologic conditions, region, contacts with sheep or cattle (known to be very common healthy carriers of D. nodosus) and existing local disease control program. We found a significant effect only of contacts with sheep having footrot. Pathogen prevalence was very low in all investigated colonies. In conclusion, our results support previous data suggesting that ibex are susceptible spillover hosts, likely infected mainly by sympatric sheep displaying clinical signs., (© Wildlife Disease Association 2021.)

Background: Little is known about the epidemiology of Toxoplasma gondii and Neospora caninum infections in alpacas (Vicugna pacos) and llamas (Lama glama) outside South America. The study aimed to estimate the seroprevalence of T. gondii and N. caninum infections in South American camelids (SAC) in Switzerland, to optimize serological tests for SAC and to identify risk factors, which may favour infection., Methods: A total of 571 sera from 132 Swiss farms (374 alpacas and 197 llamas, mean 4.3 animals/farm) were obtained. Four commercial enzyme-linked immunosorbent assays (ELISA) for detecting antibodies against T. gondii (ID Screen ® Toxoplasmosis Indirect (TOXO-MS)) or N. caninum (i.e. ID Screen ® Neospora caninum Indirect Multi-species (NCS-MS); ID Screen ® Neospora caninum Competition (NCC) and ID Screen ® Neospora caninum Indirect (NCS)) were first assessed for their use on SAC comparing their results with those in immunoblot, and optimizing cut-offs. Subsequently, two kits (TOXO-MS and NCS-MS) were selected for seroprevalence estimation. Additionally, a risk factor analysis for infection was performed on 41 farms, which agreed to participate in a web-based survey., Results: Three kits (TOXO-MS, NCS-MS and NCC) showed almost perfect agreement (kappa > 0.901) with immunoblot results when the cut-offs were optimized, and one kit (NCS) proved not to be useful for detecting N. caninum seropositive SAC. By TOXO-MS ELISA, 82.3% (308/374) of the alpacas and 84.8% (167/197) of the llamas were seropositive for T. gondii, and 131/132 (99.2%) farms had seropositive animals. By NCS-MS ELISA, 3.5% (13/374) of the alpacas and 2.5% (5/197) of the llamas evidenced antibodies against N. caninum, and 9.1% (12/132) of the farms had seropositive animals. The variables "age" and "female sex" were identified as risk factors for T. gondii infection and "absence of cats in the farm during the last two years" as a protective factor. No risk or protective factors for N. caninum infection could be identified., Conclusions: This nationwide cross-sectional study demonstrated for the first time the presence of antibodies against T. gondii and N. caninum in the Swiss SAC population, highlighting a high seroprevalence for T. gondii, the presence of cats as a risk factor and suggesting that SAC meat might represent an additional infection source for humans.

Footrot is a contagious foot disease caused by the bacterium Dichelobacter nodosus (D. nodosus) that affects sheep worldwide. Due to substantial economic and welfare impact, various countries have developed control programs against footrot. The aim of this cross-sectional study was to estimate the national prevalence of virulent and benign D. nodosus in Switzerland in the four domestic ruminant species sheep, cattle, goats and South American camelids (SAC) to detect potential host populations and to propose targeted disease control measures. Risk factors for infection with the virulent strain of D. nodosus, based on a survey carried out among farmers, were investigated on animal and herd level. Overall, 613 farms and 2920 animals were investigated during 2017-18 applying a two-stage cluster sampling strategy. A Real-Time PCR method for simultaneous detection of virulent and benign strains of D. nodosus was used for the first time in such a large study. On animal level, the true prevalence (TP) of virulent D. nodosus in sheep was estimated at 16.9% (95% confidence interval (CI 95 %): 9.5-24.3%). In cattle and goats no virulent D. nodosus was detected and in SAC an apparent prevalence (AP) of 0.2% (CI 95 %: 0.0-0.4%) was observed. On farm level, a TP of virulent D. nodosus of 16.2% (CI 95 %: 8.4-25.2%) for sheep and an AP of 1.5% (CI 95 %: 0.3-5.2%) for SAC herds was estimated. Since the Swiss control program only targets the virulent strains of D. nodosus, it was concluded that cattle, goats and SAC do not play a role in footrot epidemiology in Switzerland. Adult sheep were at higher risk of infection for virulent D. nodosus compared to lambs and yearlings. On herd level, risk factors for infection with virulent D. nodosus in sheep were earlier occurence of footrot, winter compared to summer and autumn, and goat contact on pasture. Liming pastures had a protective effect on D. nodosus infection. For benign D. nodosus, the TP in sheep was 6.3% (CI 95 %: 1.6-11.0%) and in cattle 88.4% (CI 95 %: 83.8-93.0%). The TP for benign D. nodosus in sheep farms was 2.8% (CI 95 %: 0.0-10.5%) and in cattle farms 95.9% (CI 95 %: 91.7-98.1%). In goat and SAC farms, the AP was 6.6% (CI 95 %: 3.4-11.5%) and 7.4% (CI 95 %: 3.8-13.1%), respectively. These findings could be relevant for wild ruminants such as Alpine ibex (Capra ibex ibex), which can develop clinical footrot after infection with benign D. nodosus. The findings of this study are crucial for assessing targeted disease control measures in Switzerland., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Footrot is a worldwide economically important, painful, contagious bacterial foot disease of domestic and wild ungulates caused by Dichelobacter nodosus. Benign and virulent strains have been identified in sheep presenting with mild and severe lesions, respectively. However, in Alpine ibex (Capra ibex ibex), both strains have been associated with severe lesions. Because the disease is widespread throughout sheep flocks in Switzerland, a nationwide footrot control program for sheep focusing on virulent strains shall soon be implemented. The aim of this cross-sectional study was to estimate the nationwide prevalence of both strain groups of D. nodosus in four wild indigenous ruminant species and to identify potential susceptible wildlife maintenance hosts that could be a reinfection source for domestic sheep. During two years (2017-2018), interdigital swabs of 1,821 wild indigenous ruminant species (Alpine ibex, Alpine chamois (Rupicapra rupicapra), roe deer (Capreolus capreolus), red deer (Cervus elaphus)) were analysed by Real-Time PCR. Furthermore, observed interspecies interactions were documented for each sample. Overall, we report a low prevalence of D. nodosus in all four indigenous wild ruminants, for both benign (1.97%, N = 36, of which 31 red deer) and virulent (0.05%, N = 1 ibex) strains. Footrot lesions were documented in one ibex with virulent strains, and in one ibex with benign strains. Interspecific interactions involving domestic livestock occurred mainly with cattle and sheep. In conclusion, the data suggest that wild ungulates are likely irrelevant for the maintenance and spread of D. nodosus. Furthermore, we add evidence that both D. nodosus strain types can be associated with severe disease in Alpine ibex. These data are crucial for the upcoming nationwide control program and reveal that wild ruminants should not be considered as a threat to footrot control in sheep in this context., Competing Interests: The authors have declared that no competing interests exist.

Here we report the discovery and partial characterization of a novel herpesvirus tentatively named Bufonid herpesvirus 1 (BfHV1) from severe dermatitis in free ranging common toads (Bufo bufo) in Switzerland. The disease has been observed in toads every year since 2014, in spring, during the mating season, at different and distant locations. The virus is found in the skin and occasionally in the brain of infected toads. The genome of the virus is at least 158 Kb long and contains at least 152 open reading frames with a minimal length of 270 nt. The genome of BfHV1 contains all the signature genes that are present in alloherpesviruses. Phylogenetic analysis based on the amino acid sequence of the DNA polymerase and terminase proteins positions the novel virus among the members of the genus Batrachovirus, family Alloherpesviridae. This is the first herpesvirus ever characterized in common toads.