Urban Wild Boars and Risk for Zoonotic Streptococcus suis, Spain.

Urban wild boars (Sus scrofa) from Barcelona, Spain, harbor great diversity of Streptococcus suis strains, including strains with the cps2 gene and with the same molecular profile as local human cases. The increasing trend of potential effective contacts for S. suis transmission is of public health concern.

Serological survey in wild boar (Sus scrofa) in Switzerland and other European countries: Sarcoptes scabiei may be more widely distributed than previously thought.

BACKGROUND: Sarcoptic mange has recently emerged in wild boar in Switzerland, raising the question of the origin of the infection. The main aim of this study was to assess the extent of exposure of the wild boar populations to Sarcoptes scabiei in Switzerland, prior to and after the detection of mange cases, to determine whether the mite has been recently introduced into the populations concerned. We performed a serological survey using a commercially available ELISA and 1056 archived blood samples of free-ranging wild boar from Switzerland. To facilitate the interpretation of the obtained data, we additionally estimated seroprevalence in wild boar populations of four other European countries (1060 samples), both from areas with confirmed clinical cases of mange and from areas without reported cases in wild boar. Lastly, we revised the evaluation of the commercial ELISA when used with wild boar sera. RESULTS: Seropositive reactions were observed for samples from all five countries and from 15 of the 16 study areas. The obtained apparent seroprevalences ranged from 0.0% (0/82; 95% confidence interval [CI]: 0.0-4.4) to 17.4% (8/46; 95% CI: 7.8-31.4). Wild boar from study areas with known clinical cases and those ≤60 kg were four times more likely to be seropositive than wild boar from areas without reported cases and > 60 kg, respectively. Optical density values did not differ between the two types of study areas among seropositive samples but were significantly lower among seronegative samples from areas without than from areas with clinical cases. No difference was observed between the two sampling periods in Switzerland. The revised ELISA specificity was 96.8% (984/1017; 95% CI: 95.5-97.7) when wild boar from areas without history of mange were considered truly negative. CONCLUSIONS: Seropositivity to S. scabiei is more frequent and occurs over a larger geographic range than expected. Data suggest that the parasite is endemic within the wild boar populations of Switzerland and other European countries but that its presence is not necessarily associated with disease occurrence. Extrinsic factors which trigger disease emergence in infected populations remain to be investigated. The applied ELISA represents a promising tool for future studies.

Characterizing the growth of Sarcoptes scabiei infrapopulations.

During the course of parasitic disease infestations, parasite population sizes change at both individual host (infrapopulation) and host population (metapopulation) levels. However, most studies only report epidemiological values for specific locations and times. In this study we analysed the dynamics of several Sarcoptes scabiei infrapopulations from experimentally infested Iberian ibex, Capra pyrenaica. We obtained mite counts by digesting small skin biopsies, which we compared with indices obtained from histopathological analyses performed on adjacent skin biopsies. We obtained the finite growth rate and the daily growth rate for the mite infrapopulations: mean ± SE = 11.53 ± 10.17 and 0.10 ± 0.08 mites/day, respectively. Mite counts derived from skin sample digestion did not correlate with the histological mite indices obtained from adjacent skin biopsies. At a metapopulational level, both indices of mite abundance were modelled using GLMMs and the factors influencing their variation are analysed and discussed. Our results suggest that mites are not distributed uniformly over the whole area of the skin lesion. Therefore, direct diagnoses of mange and mite counts could be inaccurate if only small skin samples are used.

Between conflict and reciprocal habituation: Human-wild boar coexistence in urban areas.

Urbanization is an ongoing global environmental change. Wildlife may respond using anthropized environments and resources, which is known as synurbization, creating human-wildlife interactions. Wild boar (Sus scrofa) populations have become common in urban areas, including the metropolitan area of Barcelona. Humans respond to wild boars in urban environments either habituating, with lower conflict perception and higher wild boar acceptance, or sensitizing, with reduced tolerance towards wild boars. Since citizen response influences conflict management, this study analysed the drivers of human responses, which should allow adopting socially-accepted measures to manage synurbic wild boar populations. Interviews to 1956 Barcelona citizens were performed, grouping the response variables to score citizen and urban characteristics, as well as citizen lay-knowledge, emotions, experiences, and perception of wild boar. Five citizen clusters were identified: cluster 1 (3.3 %), highly habituated and active wild boar feeder; cluster 2 (11.3 %), habituated to wild boars with positive feelings; cluster 3 (19.8 %), not habituated nor sensitized, willing to maintain urban wild boar populations; cluster 4 (29.1 %), sensitized and concerned, defending to reduce wild boar; and cluster 5 (40.1 %), highly sensitized and proposing to reduce or even eliminate wild boar. Positive attitudes associated wild boar to aesthetic value, closeness to nature and sympathy, and were more frequent in young citizens with urban background and high education, animal lovers habituated to wild boar through contact without negative experiences. Conversely, negative attitudes were concerned about city fouling, safety or health, accepted lethal management measures, and were more frequent in older citizens with rural background, lower education, low contact with wild boar or sensitized through negative experiences. We document for the first time the sensitization and reciprocal habituation of humans to wild boar in urban areas. The identification of the drivers of citizen attitudes towards urban wildlife should be useful to design socially-accepted management measures.

Endemic maintenance of human-related hepatitis E virus strains in synurbic wild boars, Barcelona Metropolitan Area, Spain.

Hepatitis E virus (HEV), shared by humans, domestic animals, and wildlife, is an emerging global public health threat. Because wild boars are a major reservoir of HEV, the new zoonotic interfaces resulting from wild boar population increase and synurbization significantly contribute to increasing the risk of zoonotic transmission of HEV. This study characterizes HEV strains of synurbic wild boars and assesses their relationship with sympatric human and domestic swine HEV strains. We analyzed the faeces of 312 synurbic wild boars collected from 2016 to 2021 in the Barcelona Metropolitan Area (BMA), where there is a high density of wild boars, and found 7 HEV-positive samples among those collected between 2019 and 2020. The molecular analysis of these isolates, along with 6 additional wild boar HEV isolates from a previous study, allowed us to establish a close phylogenetic relationship between these HEV strains and human HEV isolates from sympatric blood donors and domestic pigs from Catalonia. HEV-positive wild boar samples belonged to piglet, juvenile and yearling individuals, but not adults, indicating the endemic maintenance of HEV in the wild boar population of the BMA by naïve young individuals. All wild boar HEV isolates in this study classified within HEV genotype 3. The results show, for the first time, a close molecular similarity between the HEV strains endemically maintained by the synurbic wild boars in the BMA and citizens from the same area and period. The data could also indicate that HEV infection presents a seasonal and interannual variability in wild boars of BMA. Further investigation is required to unveil the HEV transmission routes between synurbic wild boars and sympatric citizens. These findings can serve in other synurbic wildlife-human interfaces throughout the world.

Mapping the risk of exposure to Crimean-Congo haemorrhagic fever virus in the Iberian Peninsula using Eurasian wild boar (Sus scrofa) as a model.

Crimean-Congo haemorrhagic fever (CCHF) virus (CCHFV) is a tick-borne zoonotic pathogen that can cause a lethal haemorrhagic disease in humans. Although the virus appears to be endemically established in the Iberian Peninsula, CCHF is an emerging disease in Spain. Clinical signs of CCHFV infection are mainly manifested in humans, but the virus replicates in several animal species. Understanding the determinants of CCHFV exposure risk from animal models is essential to predicting high-risk exposure hotspots for public health action. With this objective in mind, we designed a cross-sectional study of Eurasian wild boar (Sus scrofa) in Spain and Portugal. The study analysed 5,291 sera collected between 2006 and 2022 from 90 wild boar populations with a specific double-antigen ELISA to estimate CCHFV serum prevalence and identify the main determinants of exposure probability. To do so, we statistically modelled exposure risk with host- and environment-related predictors and spatially projected it at a 10 × 10 km square resolution at the scale of the Iberian Peninsula to map foci of infection risk. Fifty-seven (63.3 %) of the 90 populations had at least one seropositive animal, with seroprevalence ranging from 0.0 to 88.2 %. Anti-CCHFV antibodies were found in 1,026 of 5,291 wild boar (19.4 %; 95 % confidence interval: 18.3-20.5 %), with highest exposure rates in southwestern Iberia. The most relevant predictors of virus exposure risk were wild boar abundance, local rainfall regime, shrub cover, winter air temperature and soil temperature variation. The spatial projection of the best-fit model identified high-risk foci as occurring in most of western and southwestern Iberia and identified recently confirmed risk foci in eastern Spain. The results of the study demonstrate that serological surveys of CCHFV vector hosts are a powerful, robust and highly informative tool for public health authorities to take action to prevent human cases of CCHF in enzootic and emergency settings.

Mycoplasma conjunctivae in domestic small ruminants from high mountain habitats in Northern Spain.

BACKGROUND: Infectious keratoconjunctivitis (IKC) is a clinical condition affecting eyes of domestic and wild Caprinae worldwide, and Mycoplasma conjunctivae is considered the primary causative agent of IKC in sheep, goats and wild Caprinae. Domestic ruminants from high mountain habitats share grazing areas with wild mountain ungulates, such as chamois (Rupicapra spp.), Alpine ibex (Capra ibex) and European mouflon (Ovis aries musimon), and domestic sheep seem to act as M. conjunctivae reservoir. In this study, the presence of M. conjunctivae in domestic sheep and goats from the two main mountain ranges of Northern Spain, the Pyrenees and the Cantabrian Mountains, has been investigated. RESULTS: Eye swabs were obtained from 439 domestic small ruminants selected from flocks that seasonally graze in alpine meadows during three consecutive years (2011-2012-2013). Seventy-nine out of the 378 domestic sheep (20.9%) tested positive to a M. conjunctivae specific real time-PCR (rt-PCR) in at least one eye, whereas all the 61 sampled domestic goats were negative. Statistically significant higher prevalence and higher proportion of infected flocks (P < 0.001) was observed in the Pyrenees (25.7%; 12 flocks out of 13), where M. conjunctivae is widespread and probably endemic in domestic sheep, than in the Cantabrian Mountains (7.8%; one flock out of six). Twenty-five sheep (three from the Pyrenees and 22 from the Cantabrian Mountains) which showed clinical signs consistent with infectious keratoconjunctivitis (IKC) were negative by rt-PCR. In contrast, 62 out of the 71 (87.3%) M. conjunctivae-positive sheep from the Pyrenees and the eight positive sheep from the Cantabrian Mountains were asymptomatic. CONCLUSIONS: This study provides rt-PCR-based evidences of M. conjunctivae maintenance in domestic sheep, as well as a relationship between prevalence in domestic sheep and previously reported M. conjunctivae and IKC in wild ruminants. Domestic goats do not seem to play an important role in the epidemiology of M. conjunctivae in alpine habitats from Northern Spain.

Monitoring bluetongue virus vectors in Andalusia (SW Europe): Culicoides species composition and factors affecting capture rates of the biting midge Culicoides imicola.

In this work, we summarize the results of captures of Culicoides species in Andalusia (S Spain) during 2007-2008. Four out of the 15 midge species-Culicoides imicola, Culicoides obsoletus complex, Culicoides pulicaris complex, and Culicoides nubeculosus-accounted for 80.7 % of captures (n = 68,190). Captures were seasonal and mostly occurred in May-November. The overall number of Culicoides specimens captured and the mean number of caught per trap were higher in 2007. We used an information-theoretic approach to analyze whether environmental factors (e.g., weather, altitude above the sea level, distance of the trap from the ground, distance to animals, and land use) affected C. imicola capture probability and success. Mean temperature and rainfall (both integrated into the Gaussen index), distance of traps to host animals, and trap height above the ground were the main factors explaining variance in capture rates in the Bluetongue Entomologic Surveillance Andalusian Program (BESAP). However, all of these patterns strongly varied among traps. As previously remarked by other authors, standardized capture methods and protocols for trap use are needed to ensure that results obtained in different geographical areas and/or periods are comparable.

Ticks on wild boar in the metropolitan area of Barcelona (Spain) are infected with spotted fever group rickettsiae.

Tick-borne pathogens (TBPs) constitute an emerging public health concern favoured by multidimensional global changes. Amongst these, increase and spread of wild boar (Sus scrofa) populations are of special concern since this species can act as a reservoir of zoonotic pathogens and promote tick abundance. Thus, we aimed to make a first assessment of the risk by TBPs resulting from wild boar and ticks in the vicinity of a highly populated area. Between 2014 and 2016, we collected spleen samples and 2256 ticks from 261 wild boars (out of 438 inspected) in the metropolitan area of Barcelona (MAB; northeast Spain). We morphologically identified four tick species: Hyalomma lusitanicum (infestation prevalence: 33.6%), Dermacentor marginatus (26.9%), Rhipicephalus sanguineus sensu lato (18.9%) and R. bursa (0.2%). Ticks were pooled according to species and individual host. A total of 180 tick pools and 167 spleen samples were screened by real-time PCR and/or reverse line blot hybridization assay for Ehrlichia sp., Anaplasma sp., Babesia sp., Rickettsia sp., Borrelia burgdorferi sensu lato and Coxiella burnetii. Seventy-two out of the 180 tick pools were positive to Rickettsia spp. (minimum prevalence of 8.7%), including Rickettsia massiliae, R. slovaca and R. raoultii. We did not detect Rickettsia spp. in wild boar spleens nor other TBPs in ticks or wild boars. Since the ticks identified can bite humans, and the recorded spotted fever group (SFG) rickettsiae are zoonotic pathogens, there is a risk of SFG rickettsiae transmission for MAB inhabitants. Our results suggest a broader distribution of H. lusitanicum, competent vector for the Crimean-Congo haemorrhagic fever virus than previously known. Wild boar is not a Rickettsia spp. reservoir according to the spleen negative results. However, its abundance could favour tick life cycle and abundance, and its proximity to humans could promote the infection risk by Rickettsia spp.

Wild boar in the city: Phenotypic responses to urbanisation.

Urbanisation is a global human-induced environmental change and one of the most important threats to biodiversity. To survive in human-modified environments, wildlife must adjust to the challenging selection pressures of urban areas through behaviour, morphology, physiology and/or genetic changes. Here we explore the effect of urbanisation in a large, highly adaptable and generalist urban adapter species, the wild boar (Sus scrofa, Linnaeus 1758). From 2005 to 2018, we gathered wild boar data and samples from three areas in NE Spain: one urban (Barcelona municipality, n = 445), and two non-urban (Serra de Collserola Natural Park, n = 183, and Sant Llorenç del Munt i Serra de l'Obac Natural Park, n = 54). We investigated whether urbanisation influenced wild boar body size, body mass, body condition, and the concentration of serum metabolites, considering also the effect of age, sex and use of anthropogenic food resources. Wild boars from the urban area had larger body size, higher body mass, better body condition, and a higher triglyceride and lower creatinine serum concentrations than non-urban wild boars. In addition, urban wild boars consumed food from anthropogenic origin more frequently, which suggests that differences in their diet probably induced the biometric and the metabolic changes observed. These responses are probably adaptive and suggest that wild boars are thriving in the urban environment. Our results show that urbanisation can change the morphological and physiological traits of a large mammal urban adapter, which may have consequences in the ecology and response to urban selection pressures by the species. The phenotypic plasticity shown by wild boars provides both further and new evidence on the mechanisms that allow urban adapter species of greater size to respond to urbanisation, which is expected to continue growing globally over the coming decades.

Detection of Beta-Lactam-Resistant Escherichia coli and Toxigenic Clostridioides difficile Strains in Wild Boars Foraging in an Anthropization Gradient.

Disease transmission among wild boars, domestic animals and humans is a public health concern, especially in areas with high wild boar densities. In this study, fecal samples of wild boars (n = 200) from different locations of the Metropolitan Area of Barcelona were analyzed by PCR to explore the frequency of ß-lactamases and extended cephalosporin and carbapenem resistance genes (ESBLs) in Escherichia coli strains and the presence of toxigenic Clostridioides difficile. The prevalence of genes conferring resistance to ß-lactam antimicrobials was 8.0% (16/200): blaCMY-2 (3.0%), blaTEM-1b (2.5%), blaCTX-M-14 (1.0%), blaSHV-28 (1.0%), blaCTX-M-15 (0.5%) and blaCMY-1 (0.5%). Clostridioides difficile TcdA+ was detected in two wild boars (1.0%), which is the first report of this pathogen in wild boars in Spain. Moreover, the wild boars foraging in urban and peri-urban locations were more exposed to AMRB sources than the wild boars dwelling in natural environments. In conclusion, the detection of E. coli carrying ESBL/AmpC genes and toxigenic C. difficile in wild boars foraging in urban areas reinforces the value of this game species as a sentinel of environmental AMRB sources. In addition, these wild boars can be a public and environmental health concern by disseminating AMRB and other zoonotic agents. Although this study provides the first hints of the potential anthropogenic sources of AMR, further efforts should be conducted to identify and control them.

Accumulation of diastereomers of anticoagulant rodenticides in wild boar from suburban areas: Implications for human consumers.

We studied the prevalence of anticoagulant rodenticides (ARs) in liver and muscle tissues of wild boar captured in the urban area of Barcelona, the suburban area of Collserola Natural Park and the rural area of Santa Quiteria, next to Cabañeros National Park, in Spain. The objective was to assess the influence of both urbanisation and wild boar (Sus scrofa) trophic opportunism on the accumulation of these compounds. We have also evaluated the risk for human consumers of this game meat. Wild boars from Barcelona city showed the highest prevalence of ARs detection (60.8%), followed by the adjoining suburban area of Collserola N.P. (40%) and the rural distant area of Santa Quiteria (7.7%). Liver bioaccumulated ARs (45.2%) more frequently than muscle (11.9%). A significant proportion (13.7%) of wild boar captured in Barcelona city exceeded 200 ng/g of total ARs in liver, a threshold for adverse effects on blood clotting. For difenacoum, there was a predominance of cis isomer, while for brodifacoum and bromadiolone cis and trans isomers appeared in a similar proportion. According to the scarce available information on ARs toxicity in humans, the risk of acute poisoning from game meat consumption seems to be low. However, repeated exposure through liver consumption should be considered in further risk assessments because of the high concentration detected in some samples (up to 0.68 mg/kg).

Systemic toxoplasmosis and Gram-negative sepsis in a southern chamois (Rupicapra pyrenaica) from the Pyrenees in northeast Spain.

A 6-year-old, male southern chamois (Rupicapra pyrenaica) had an absence of flight response and was captured by hand in the Catalan Pyrenees in northeast Spain. On clinical examination, the animal was in good body condition, and only atrophy of the right eye was observed. Blood samples were collected and hematologic analysis performed, but no alterations were observed. The animal was sent to a Wildlife Rescue Centre, where it developed chronic wasting and died after 32 days in captivity. At necropsy, the animal was cachectic and had edematous, mottled lungs. Histopathologic examination revealed systemic toxoplasmosis and acute Gram-negative septicemia. The protozoan organisms were identified as Toxoplasma gondii based on immunohistochemistry. An indirect fluorescent antibody test was performed, and the animal was positive with an antibody titer of 150.

Blood chemistry and hematologic values in free-living nestlings of Montagu's harriers (Circus pygargus) in a natural habitat.

The establishment of reference intervals for hematologic and blood chemistry values in a given species is essential for subsequent diagnosis of disease at rehabilitation facilities and in captive breeding programs. In this study, blood samples were obtained from nestlings (18 males and 22 females) of a natural-vegetation breeding population of Montagu's harrier (Circus pygargus) in eastern Spain in order to establish reference intervals for blood values. This is the first study documenting hematologic and biochemical reference intervals for free-living Montagu's harriers. The studied population may reflect typical blood values for the species, since it is a free-living population that seems not to be constrained by food availability, as it is the population of Montagu's harriers with the highest productivity within Europe. Differences related to sex, year, clutch size, brood size, and number of fledglings were analyzed. Packed cell volume and hemoglobin were significantly lower from nests with five chicks compared to values from nests with fewer chicks, indicating that the cost of rearing more than four chicks in this species may be excessive. Total protein, calcium (Ca), and phosphorus (P) were significantly lower in the year with lowest mean rainfall, which correlates with the worst breeding success rate since the population has been monitored. No gender differences were found; this is likely a result of the prepubertal age of the animals sampled.

Genetically similar hepatitis E virus strains infect both humans and wild boars in the Barcelona area, Spain, and Sweden.

Hepatitis E virus (HEV) is a hepatotropic virus, endemic in Europe where it infects humans and animals, with domestic pigs and wild boars as main reservoirs. The number of HEV-infected cases with unknown source of infection increases in Europe. There are human HEV strains genetically similar to viruses from domestic pigs, and zoonotic transmission via consumption of uncooked pork meat has been shown. Due to continuous growth of the wild boar populations in Europe, another route may be through direct or indirect contacts with wild boars. In the Collserola Natural Park near Barcelona, Spain, the wild boars have spread into Barcelona city. In Sweden, they are entering into farmlands and villages. To investigate the prevalence of HEV and the risk for zoonotic transmissions, the presence of antibodies against HEV and HEV RNA were analysed in serum and faecal samples from 398 wild boars, 264 from Spain and 134 from Sweden and in sera from 48 Swedish patients with HEV infection without known source of infection. Anti-HEV was more commonly found in Spanish wild boars (59% vs. 8%; p < 0.0001) while HEV RNA had similar prevalence (20% in Spanish vs. 15% in Swedish wild boars). Seven Swedish and three Spanish wild boars were infected with subtype 3f, and nine Spanish with subtype 3c/i. There were three clades in the phylogenetic tree formed by strains from wild boars and domestic pigs; another four clades were formed by strains from humans and wild boars. One strain from a Spanish wild boar was similar to strains from chronically infected humans. The high prevalence of HEV infections among wild boars and the similarity between wild boar HEV strains and those from humans and domestic pigs indicate that zoonotic transmission from wild boar may be more common than previously anticipated, which may develop into public health concern.

Urban wild boars prefer fragmented areas with food resources near natural corridors.

Wild boar populations are expanding throughout the world and intruding into periurban and urban areas. In the last years, wild boar has colonized several European cities, including our study area, the city of Barcelona. It is required to identify the main factors driving wild boar into urban areas prior to establish management measures. We built Boosted Regression Trees (BRT) using 3148 wild boar presences registered in the urban area of Barcelona from 2010 to 2014 to identify the variables correlated with these presences. The variables analysed included proxies for distance to source population, urban food resources, climate and urban habitat structure. Wild boars enter the urban area from close natural habitat using corridors such as streams, preferably in fragmented urban environment, looking for food such as urban green areas or dry pet food from cat colonies. Wild boar presence is higher in spring possibly due to the births of piglets and the dispersion of yearlings during that season, and also when natural resources in the Mediterranean habitat fail to satisfy the nutritional requirements of the wild boar population during the summer season. Management measures derived from this study are currently being applied in the city of Barcelona, including vegetation clearings in the wild boar entrance areas and an awareness campaign aimed at reducing the anthropogenic food availability for wild boars. The methodology used can be applied to other cities with wild boar or even other wildlife species issues. The comparison between the factors attracting wild boars into different urban areas would be helpful to understand the global phenomenon.

Effects of acepromazine on the stress response in Southern chamois (Rupicapra pyrenaica) captured by means of drive-nets.

This study was conducted to assess the stress response of Southern chamois (Rupicapra pyrenaica) to capture and physical restraint and the effects of acepromazine (a short-acting neuroleptic) on this response. Forty free-ranging Southern chamois were captured, injected intramuscularly with acepromazine (19 animals, randomly selected) or saline (the other 21 animals), and physically restrained for 3 h. Heart rate and body temperature were monitored with telemetric devices, and blood samples were obtained at capture and every hour thereafter to determine hematologic and serum biochemical parameters. The lower heart-rate variability, temperature, erythrocyte count, hemoglobin concentration, packed cell volume (PCV), and serum creatine kinase activity in the animals treated with acepromazine indicated that this agent reduced the adverse effects of stress. According to the differences in heart rate, erythrocyte count, hemoglobin concentration, PCV, lymphocyte count, and serum concentrations of glucose, creatinine, chloride, and potassium, alpha-adrenergic stimulation by catecholamines seemed to be stronger in females, whereas the adrenal-cortex reaction seemed to be stronger in males. The differences in erythrocyte parameters, temperature, serum creatine kinase activity, and serum concentrations of potassium and chloride indicated that acepromazine's beneficial effects were greater in females.

Evaluation of oxidant/antioxidant balance in Iberian ibex (Capra pyrenaica) experimentally infested with Sarcoptes scabiei.

Oxidative stress (OS) is an imbalance between radical-generating and radical scavenging activity, resulting in oxidation products and tissue damage. Although some studies have been done in other species, there is a lack of information about the oxidative/antioxidant status in the Iberian ibex (Capra pyrenaica) affected by sarcoptic mange. To clarify this fact, albumin, catalase (CAT), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), paraoxonase-1 (PON-1), glutathione reductase (GR), reduced glutathione (GSH): oxidized glutathione (GSSG) ratio, thiobarbituric acid reactive substances (TBARS) and total oxidant status (TOS) concentrations were measured in peripheral blood of ibexes experimentally infested with Sarcoptes scabiei (n=25), as well as in the healthy control group (n=14). During the course of the experiment, the infected ibexes were visually assigned to four categories according to the percentage of skin surface affected by mites. In the infested ibexes, the levels of albumin, PON-1, CAT, SOD, GSH-Px and GSH:GSSG ratio showed a significant (p<0.01) decrease with disease progression. With respect to the control group, this decrease was significantly (p<0.001) lower in the more severe clinical stages. No significant changes were observed in GR activity during disease or with respect to the control group. Conversely, the concentrations of TOS and TBARS increased with lesion severity, and with respect to the control group, this increase was significant (p<0.01) in the more advanced stages of the infection. Additionally, to explore the possible effects of sex, age, haplotype, mange status, and days post infection (dpi) on each of the OS biomarkers, generalized additive mixed models were applied. According to our results, the mange status and dpi explained the highest percentages in the observed changes in the biomarkers analyzed, whereas the haplotype only influenced the observed variability of albumin and TOS. The contribution of sex and age was not significant in any of the OS biomarkers. From the present study, it may be concluded that sarcoptic mange infestation increases OS and decreases antioxidant status in ibex. This imbalance may contribute to the pathogenesis of this disease.

Sarcoptes scabiei alters follicular dynamics in female Iberian ibex through a reduction in body weight.

Normal development of the ovarian cycle is a key factor in ensuring female reproductive success. Sarcoptes scabiei has been shown to induce changes in host physiology, although the effects of this mite on the female reproductive cycle are still unknown. In an attempt to clarify this issue, the number of ovarian structures (primary follicles, secondary follicles, Graaf follicles, corpus luteum and corpus albicans) in female Iberian ibex (Capra pyrenaica) affected by sarcoptic mange was explored by histological analysis of samples taken from 102 females selectively harvested in the Sierra Nevada Natural Space, southern Spain. The effect of mange status, body weight (corrected for age), age and year of sampling on the number of ovarian structures was assessed using generalized linear models. Our results provide evidence that sarcoptic mange alters follicular dynamics through a reduction in host body weight, whose main consequences are noted in follicular maturation and ovulatory capacity.