Wild bird species have commonly been implicated as potential vectors of pathogens to other species, humans included. However, the habitat where birds live could influence the probability to acquire these pathogens. Here, we evaluated if the characteristics of the environment used by obligate scavenging birds (vultures) influence their colonization by zoonotic pathogens. For this, we particularly focused on Salmonella spp., a zoonotic pathogen commonly present in bird species. The occurrence of this bacteria was evaluated in free ranging Andean condors (Vultur gryphus) using natural environments from Argentina and compared with those obtained from condors under human care. In addition, we compared our results with those reported for other wild vultures using natural and anthropized environments at a global scale. We did not find Salmonella spp. in samples of wild condors. Captive condor samples presented Salmonella spp. with an occurrence of 2.8%, and one isolate of Meticilin Resistant Staphylococcus aureus, among other potential pathogenic microorganisms. Moreover, some species of free ranging vultures from diverse geographical areas using anthropized environments tend to present higher occurrences of Salmonella spp. These results highlight the importance of pristine ecosystems to protect vultures’ health toward pathogenic microorganisms that can produce disease in these birds, but also in other species. We call for more studies evaluating differences in occurrence of zoonotic pathogens in vultures according to the quality of the environment they use. Even when vultures have not been implicated in zoonotic pathogen spread, our results add information to evaluate potential events of pathogen spillover between vultures and from these birds to other species.

The aim of the study was to investigate the intramuscular pharmacokinetics of enrofloxacin in black vultures (Coragyps atratus). The pharmacokinetics of a single intramuscular dose (10 mg/kg) of enrofloxacin was studied in six vultures. Plasma concentrations of enrofloxacin and its active metabolite, ciprofloxacin, were determined by high-performance liquid chromatography (HPLCuv). Pharmacokinetic parameters were estimated using non-compartmental and compartmental analysis. After intramuscular administration, enrofloxacin showed a rapid and complete absorption, reaching a Cmax value of 3.26 ± 0.23 μg/mL at 1.75 ± 0.53 h. A long terminal half-life of 19.58 h has been observed. Using previously published MIC values to perform a PK/PD analysis, cumulative fraction responses obtained after Monte Carlo simulation for AUC/MIC > 30, 50 and 125 were 72.93%, 72.34% and 30.86% for E. coli and 89.29%, 88.89% and 58.57% for Mycoplasma synoviae, respectively. Cumulative fraction responses obtained for Cmax/MIC index were 33.93% and 40.18% for E. coli and M. synoviae, respectively. The intramuscular administration of 10 mg/kg could be appropriate to treat infectious diseases caused by gram-positive bacteria with MIC value lower than 1 µg/mL; however, although enrofloxacin showed a slow elimination in black vultures, plasma concentrations were insufficient to reach the gram-negative stablished breakpoints.

Disease risk management is essential for conservation translocations to prevent inadvertent pathogen introduction affecting human, animal and ecosystem health. Wildlife Disease Risk Analysis (DRA) is a recognized framework for addressing health hazards in translocations. However, DRA is not mandatory nor voluntarily applied in Argentina, despite increasing wildlife translocations. To test and adapt DRA to the local context, we performed a simplified DRA for the hypothetical translocation of marsh deer (Blastocerus dichotomus) between two protected areas, Iberá and El Impenetrable National Parks. A multidisciplinary team applied the main phases of DRA, problem description, hazard identification, risk assessment and mitigation, to this scenario. Out of 61 potential hazards identified, including pathogens and management issues, 14 priority hazards were highlighted using a paired risk prioritization tool. Of these, 66% have zoonotic potential. Presence of Ehrlichia chaffeensis at the source (Iberá) but not the destination park signalled unacceptable risk under a One Health perspective. All other hazards, including pathogens, stress and seasonal factors, were considered manageable through strategic planning and mitigation actions. This study represents the first application of DRA to conservation translocations in Argentina, in a context of data and resource limitations. Strengthening baseline information and stakeholder engagement would enhance its utility. DRA findings should inform broader ecological evaluations to assess feasibility and relevance of translocations. We advocate for the integration of DRA into conservation planning in Argentina and South America, even under suboptimal conditions.