Management of Suspected Cases of Feline Immunodeficiency Virus Infection in Eurasian Lynx (Lynx lynx) During an International Translocation Program.

The Eurasian lynx (Lynx lynx) population in Switzerland serves as a source for reintroductions in neighboring countries. In 2016-2017, three lynx from the same geographical area were found seropositive for feline immunodeficiency virus (FIV) in the framework of an international translocation program. This novel finding raised questions about the virus origin and pathogenicity to lynx, the emerging character of the infection, and the interpretation of serological results in other lynx caught for translocation. Archived serum samples from 84 lynx captured in 2001-2016 were retrospectively tested for FIV antibodies by Western blot. All archived samples were FIV-negative. The three seropositive lynx were monitored in quarantine enclosures prior to euthanasia and necropsy. They showed disease signs, pathological findings, and occurrence of co-infections reminding of those described in FIV-infected domestic cats. All attempts to isolate and characterize the virus failed but serological data and spatiotemporal proximity of the cases suggested emergence of a lentivirus with antigenic and pathogenic similarities to FIV in the Swiss lynx population. A decision scheme was developed to minimize potential health risks posed by FIV infection, both in the recipient and source lynx populations, considering conservation goals, animal welfare, and the limited action range resulting from local human conflicts. Development and implementation of a cautious decision scheme was particularly challenging because FIV pathogenic potential in lynx was unclear, negative FIV serological results obtained within the first weeks after infection are unpredictable, and neither euthanasia nor repatriation of multiple lynx was acceptable options. The proposed scheme distinguished between three scenarios: release at the capture site, translocation, or euthanasia. Until April 2021, none of the 40 lynx newly captured in Switzerland tested FIV-seropositive. Altogether, seropositivity to FIV was documented in none of 124 lynx tested at their first capture, but three of them seroconverted in 2016-2017. Diagnosis of FIV infection in the three seropositive lynx remains uncertain, but clinical observations and pathological findings confirmed that euthanasia was appropriate. Our experiences underline the necessity to include FIV in pathogen screenings of free-ranging European wild felids, the importance of lynx health monitoring, and the usefulness of health protocols in wildlife translocation

Challenges in Whole Exome Sequencing: An Example from Hereditary Deafness

Whole exome sequencing provides unprecedented opportunities to identify causative DNA variants in rare Mendelian disorders. Finding the responsible mutation via traditional methods in families with hearing loss is difficult due to a high degree of genetic heterogeneity. In this study we combined autozygosity mapping and whole exome sequencing in a family with 3 affected children having nonsyndromic hearing loss born to consanguineous parents. Two novel missense homozygous variants, c.508C>A (p.H170N) in GIPC3 and c.1328C>T (p.T443M) in ZNF57, were identified in the same ∼6 Mb autozygous region on chromosome 19 in affected members of the family. Both variants co-segregated with the phenotype and were absent in 335 ethnicity-matched controls. Biallelic GIPC3 mutations have recently been reported to cause autosomal recessive nonsyndromic sensorineural hearing loss. Thus we conclude that the hearing loss in the family described in this report is caused by a novel missense mutation in GIPC3. Identified variant in GIPC3 had a low read depth, which was initially filtered out during the analysis leaving ZNF57 as the only potential causative gene. This study highlights some of the challenges in the analyses of whole exome data in the bid to establish the true causative variant in Mendelian disease

Phylogenomic analyses of malaria parasites and evolution of their exported proteins

<p>Abstract</p> <p>Background</p> <p><it>Plasmodium falciparum </it>is the most malignant agent of human malaria. It belongs to the taxon Laverania, which includes other ape-infecting <it>Plasmodium </it>species. The origin of the Laverania is still debated. <it>P. falciparum </it>exports pathogenicity-related proteins into the host cell using the <it>Plasmodium </it>export element (PEXEL). Predictions based on the presence of a PEXEL motif suggest that more than 300 proteins are exported by <it>P. falciparum</it>, while there are many fewer exported proteins in non-Laverania.</p> <p>Results</p> <p>A whole-genome approach was applied to resolve the phylogeny of eight <it>Plasmodium </it>species and four outgroup taxa. By using 218 orthologous proteins we received unanimous support for a sister group position of Laverania and avian malaria parasites. This observation was corroborated by the analyses of 28 exported proteins with orthologs present in all <it>Plasmodium </it>species. Most interestingly, several deviations from the <it>P. falciparum </it>PEXEL motif were found to be present in the orthologous sequences of non-Laverania.</p> <p>Conclusion</p> <p>Our phylogenomic analyses strongly support the hypotheses that the Laverania have been founded by a single <it>Plasmodium </it>species switching from birds to African great apes or <it>vice versa</it>. The deviations from the canonical PEXEL motif in orthologs may explain the comparably low number of exported proteins that have been predicted in non-Laverania.</p

A tooth wear scoring scheme for age estimation of the Eurasian lynx (Lynx lynx) under field conditions

Within the framework of conservation actions for the Eurasian lynx (Lynx lynx), ageing of individuals is required to assess suitability for translocation and to investigate population dynamics and disease epidemiology. We aimed to develop a standardised ageing tool for free-ranging Eurasian lynx, which would be non-invasive, time- and cost-effective, and applicable under field conditions. We used tooth pictures of 140 free-ranging lynx of known age from Switzerland. Tooth colour, calculus, number of incisor teeth and canine, premolar and molar tooth wear were recorded according to pre-defined criteria. Statistical comparisons among the categories of each criterion revealed significant differences for all criteria. Tooth colour and canine tooth morphology showed obvious and consistent alterations with age. Together with the molar tooth shape, premolar tooth tips, incisor teeth and amount of calculus, they pictured the age-related changes in lynx dentition. Crown fractures, enamel flaking and open pulp cavities were observed with an increasing prevalence over age but were also sporadically seen in juveniles. Based on the obtained results, we developed a classification scheme distinguishing six age classes: < 1 year, 1–2 years, 3–6 years, 7–9 years, 10–13 years, ≥ 14 years. The scheme was subsequently tested with the same lynx. Classification success rates of different readers ranged from 69 to 88% but errors did not exceed one age class. The homogenous tooth replacement pattern observed in lynx < 1 year allowed us to develop a separate ageing chart to age juveniles in months. The proposed scheme is a promising tool to objectively assign lynx to meaningful age categories

Morphometric characteristics of free-ranging Eurasian lynx Lynx lynx in Switzerland and their suitability for age estimation

Knowledge of the age of individual animals is crucial to assess population dynamics, disease epidemiology and to successfully implement conservation strategies. Morphometric data reflect complex interactions of factors such as age and sex, and may also depend on genetics, population density, food availability, pathogen load and climate. The aims of this study were to assess the suitability of morphometric characteristics as an ageing tool for lynx during their growth period and to provide baseline data for the Eurasian lynx populations in Switzerland. Seventeen body measurements of 180 free-ranging Eurasian lynx (Lynx lynx) of known age, captured or found dead in Switzerland between 1981-2017 were compiled by sex and age class (juveniles, subadults, adults) and tested for significant differences between males and females, age classes, and populations (Jura Mountains, Alps). Classification tree analysis (CART) was performed to create an ageing tool based on physical characteristics. Generalised linear models revealed a significant effect of age and sex on measurements but no differences were found between populations. The growth pattern was characterised by a rapid increase of all parameters in the first year of life, followed by a slowdown in the subadult age class; the adult class corresponded to the post-growth period. Sex differences became apparent at the age of 9-11 months and were most pronounced in adults. The developed classification trees allowed us to correctly categorise 93% of the females and 92% of males as juvenile, subadult or adult. In conclusion, classification trees based on body measurements can be used to place lynx into broad age categories and represent a standardised, non-invasive, fast, cost-free and very user-friendly tool. These trees can be successfully combined with tooth wear evaluation and deliver age information with an accuracy acceptable in the context of various epidemiological investigations and the selection of individuals for translocation

Severe Conjunctivitis Associated with Chlamydia felis Infection in a Free-ranging Eurasian Lynx ( Lynx lynx).

A free-ranging adult Eurasian lynx ( Lynx lynx) captured in Switzerland presented with a severe purulent unilateral conjunctivitis. Chlamydia felis was detected in conjunctival swabs by qPCR. Systemic treatment with oxytetracycline and ketoprofen led to complete recovery. Infection with C. felis has not been previously reported in Eurasian lynx

Analysis of a European general wildlife health surveillance program: Chances, challenges and recommendations.

In a One Health perspective general wildlife health surveillance (GWHS) gains importance worldwide, as pathogen transmission among wildlife, domestic animals and humans raises health, conservation and economic concerns. However, GWHS programs operate in the face of legal, geographical, financial, or administrative challenges. The present study uses a multi-tiered approach to understand the current characteristics, strengths and gaps of a European GWHS that operates in a fragmented legislative and multi-stakeholder environment. The aim is to support the implementation or improvement of other GWHS systems by managers, surveillance experts, and administrations. To assess the current state of wildlife health investigations and trends within the GWHS, we retrospectively analyzed 20 years of wildlife diagnostic data to explore alterations in annual case numbers, diagnosed diseases, and submitter types, conducted an online survey and phone interviews with official field partners (hunting administrators, game wardens and hunters) to assess their case submission criteria as well as their needs for post-mortem investigations, and performed in-house time estimations of post-mortem investigations to conduct a time-per-task analysis. Firstly, we found that infectious disease dynamics, the level of public awareness for specific diseases, research activities and increasing population sizes of in depth-monitored protected species, together with biogeographical and political boundaries all impacted case numbers and can present unexpected challenges to a GWHS. Secondly, we found that even a seemingly comprehensive GWHS can feature pronounced information gaps, with underrepresentation of common or easily recognizable diseases, blind spots in non-hunted species and only a fraction of discovered carcasses being submitted. Thirdly, we found that substantial amounts of wildlife health data may be available at local hunting administrations or disease specialist centers, but outside the reach of the GWHS and its processes. In conclusion, we recommend that fragmented and federalist GWHS programs like the one addressed require a central, consistent and accessible collection of wildlife health data. Also, considering the growing role of citizen observers in environmental research, we recommend using online reporting systems to harness decentrally available information and fill wildlife health information gaps