Sarcoptic mange in wild ruminants in zoological gardens in Israel

Novel Theileria sp. as an Etiology of Cutaneous Theileriosis among the Vulnerable Arabian Oryx

The Arabian Peninsula's endemic ungulate, Oryx leucoryx, was on the verge of extinction at the end of the 1970s. Despite the different reintroduction programs, the International Union for Conservation of Nature is still classifying it as Vulnerable. Among other factors, their vulnerability lies in their susceptibility to specific etiological agents that affect livestock, necessitating health monitoring and strict preventive/biosecurity measures. Within this frame, the current work investigated the determination of the etiological agent potentially involved with cutaneous lesions observed in eight males of Arabian oryx within one of the several national governance conservation programs. Microscopic examination from one animal specimen suggested theileriosis association, which was confirmed by molecular tools using 18S gene sequencing and the report of a novel Theileria sp. not clustering with previously reported antelope sequences. This finding prompts further explorations into the disease dynamics within the Arabian oryx population, especially with the scarcity of data in Qatar about tick-borne pathogens and their transmission.

Sarcoptes scabiei infestation in a captive lowland tapir (Tapirus terrestris): case report, morphological and molecular genetic mite identification

Sarcoptes scabiei (Acari: Sarcoptidae) is a globally distributed parasitic mite species, which causes mange in a broad spectrum of domestic and wild mammals. In the present study, we report a case of chronic S. scabiei infestation in a captive lowland tapir (Tapirus terrestris) held in a multi-species exhibit at Vienna Zoo. The adult male showed clinically manifested mange flare-ups three times at an interval of up to 12 months, diagnosed by positive deep-skin scrapings and successfully treated by oral applications of ivermectin (0.1-0.2 mg/kg body weight) and washings with antimicrobial solutions. Clinical symptoms including pruritus, alopecia, erythema, crusts, and superficial bleedings were limited to the axillar and pectoral region, as well as distal limbs. The affected tapir died from underlying bacterial pneumonia during general anesthesia. Skin scrapings, necropsy, and histopathological analysis of mite material (eggs, larvae, and adults) permitted further morphological and molecular identification. The morphological features described here matched the characteristics for the species S. scabiei and molecular data verified morphological identification. Cross-species transmission plays a key role in the expansion of this neglected emerging panzootic disease and urban wildlife could potentially bridge the gap between free-ranging wildlife reservoirs and zoo animals. However, further examinations are needed to detect the primary source of infestation and discover transmission pathways within the zoo.

An Outbreak of Sarcoptic Mange in Free-Ranging Arabian Oryx (Oryx leucoryx) in the United Arab Emirates, and Treatment with Ivermectin-Medicated Pelleted Feed

At a visit to an unfenced desert conservation reserve in Dubai, United Arab Emirates in February 2022, severe skin disease was noted among resident Arabian oryx (Oryx leucoryx), manifesting as dark grayish to black bark-like thickened skin. Between and 45% and 60% of the oryx showed unrest and pruritus. Sarcoptes scabiei was detected at necropsy of six adult animals. Treatment with ivermectin-medicated pellets at 0.3 mg/kg estimated body weight over two periods of 7 d with a 14-d interval between treatments resulted in improved body and skin condition and hair regrowth. Although severe hyperkeratosis was still present shortly after treatment, no live Sarcoptes mites were found in parasitological examination of skin scrapings of two necropsied animals. By 4 mo post treatment the oryx had returned to normal body condition and coat condition.

Ivermectin Plasma Concentration in Iberian Ibex (Capra pyrenaica) Following Oral Administration: A Pilot Study

Sarcoptic mange is considered the main driver of demographic declines occurred in the last decades in Iberian ibex (Capra pyrenaica) populations. Mass treatment campaigns by administration of in-feed acaricides are used as a measure to mitigate the impact of mange in the affected populations. However, there are no data on ivermectin (IVM) pharmacokinetics in this wild caprine, and the treatment through medicated feed is not endorsed by evidence on its effectiveness. The aim of this study is to determine the pharmacokinetic profile of IVM in plasma samples of ibexes after the experimental oral administration of IVM, using high performance liquid chromatography (HPLC) with automated solid phase extraction and fluorescence detection. A dose of 500 μg of IVM per body weight was orally administered in a feed bolus to nine healthy adult ibexes (seven males and two females). Blood samples were collected by jugular venipuncture into heparin-coated tubes at day 1, 2, 3, 4, 7, 10, 15, and 45 post-administration (dpa). The highest plasma concentration of IVM (Cmax = 3.4 ng/ml) was detected 24 h after the oral administration (T1), followed by a rapid decrease during the first week post-administration. Our results reveal that plasma IVM concentration drops drastically within 5 days of ingestion, questioning the effectiveness of a single in-feed dose of this drug to control sarcoptic mange. To the best of our knowledge, this is the first study on plasma availability of oral IVM in ibexes and in any wild ungulate species.

Sustaining Transmission in Different Host Species: The Emblematic Case of Sarcoptes scabiei

Some pathogens sustain transmission in multiple different host species, but how this epidemiologically important feat is achieved remains enigmatic. Sarcoptes scabiei is among the most host generalist and successful of mammalian parasites. We synthesize pathogen and host traits that mediate sustained transmission and present cases illustrating three transmission mechanisms (direct, indirect, and combined). The pathogen traits that explain the success of S. scabiei include immune response modulation, on-host movement capacity, off-host seeking behaviors, and environmental persistence. Sociality and host density appear to be key for hosts in which direct transmission dominates, whereas in solitary hosts, the use of shared environments is important for indirect transmission. In social den-using species, combined direct and indirect transmission appears likely. Empirical research rarely considers the mechanisms enabling S. scabiei to become endemic in host species—more often focusing on outbreaks. Our review may illuminate parasites’ adaptation strategies to sustain transmission through varied mechanisms across host species.

The treatment of sarcoptic mange in wildlife: a systematic review

BACKGROUND

Sarcoptic mange, caused by the Sarcoptes scabiei mite, is an infectious disease of wildlife, domestic animals and humans with international importance. Whilst a variety of treatment and control methods have been investigated in wildlife, the literature is fragmented and lacking consensus. The primary objectives of this review were to synthesise the diverse literature published on the treatment of sarcoptic mange in wildlife from around the world, and to identify the qualities of successful treatment strategies in both captive and free-roaming wildlife.

METHODS

A systematic search of the electronic databases CAB Direct, PubMed, Scopus, Web of Science, EMBASE and Discovery was undertaken. Data pertaining to study design, country, year, species, study size, mange severity, treatment protocol and outcomes were extracted from eligible studies and placed in a table. Following data extraction, a decision tree was used to identify studies suitable for further analysis based on the effectiveness of their treatment protocol, whether they were conducted on captive or non-captive wildlife, and the quality of their post-treatment monitoring period.

RESULTS

Twenty-eight studies met our initial inclusion criteria for data collection. Of these studies, 15 were selected for further analysis following application of the decision tree. This comprised of 9 studies on captive wildlife, 5 studies on free-living wildlife and 1 study involving both captive and free-living wildlife. Ivermectin delivered multiple times via subcutaneous injection at a dose between 200-400 µg/kg was found to be the most common and successfully used treatment, although long-term data on post-release survival and re-infection rates was elusive.

CONCLUSIONS

To our knowledge, this review is the first to demonstrate that multiple therapeutic protocols exist for the treatment of sarcoptic mange in wildlife. However, several contemporary treatment options are yet to be formally reported in wildlife, such as the use of isoxazoline chemicals as a one-off treatment. There is also a strong indication for more randomised controlled trials, as well as improved methods of post-treatment monitoring. Advancing this field of knowledge is expected to aid veterinarians, wildlife workers and policy makers with the design and implementation of effective treatment and management strategies for the conservation of wildlife affected by sarcoptic mange.

First detection of Sarcoptes scabiei from domesticated pig (Sus scrofa) and genetic characterization of S. scabiei from pet, farm and wild hosts in Israel

In this report we describe for the first time the detection of Sarcoptes scabiei type suis mites on domestic pigs in Israel and examine its genetic variation compared with S. sabiei from other hosts. Microscopic examination of skin samples from S. scabiei-infested pigs (Sus scrofa domesticus) revealed all developmental stages of S. scabiei. To detect genetic differences between S. scabiei from different hosts, samples obtained from pig, rabbits (Orictolagus cuniculus), fox (Vulpes vulpes), jackal (Canis aureus) and hedgehog (Erinaceus concolor) were compared with GenBank-annotated sequences of three genetic markers. Segments from the following genes were examined: cytochrome C oxidase subunit 1 (COX1), glutathione-S-transferase 1 (GST1), and voltage-sensitive sodium channel (VSSC). COX1 analysis did not show correlation between host preference and genetic identity. However, GST1 and VSSC had a higher percentage of identical sites within S. scabiei type suis sequences, compared with samples from other hosts. Taking into account the limited numbers of GST1 and VSSC sequences available for comparison, this high similarity between sequences of geographically-distant, but host-related populations, may suggest that different host preference is at least partially correlated with genetic differences. This finding may help in future studies of the factors that drive host preferences in this parasite.

First description of gastrointestinal nematodes of Barbary sheep (Ammotragus lervia): the case of Camelostrongylus mentulatus as a paradigm of phylogenic and specific relationship between the parasite and its ancient host

The gastrointestinal helminth fauna of 24 Barbary sheep or Aoudad (Ammotragus lervia sahariensis) maintained in the Parque de Rescate de la Fauna Sahariana (PRFS, CSIC, Almeria, Spain) was analyzed. Most animals (87.5 %) were parasitized, and multiple infections were highly present. The following species were identified: Camelostrongylus mentulatus, Teladorsagia circumcincta, Marshallagia marshalli, Ostertagia ostertagi, O. leptospicularis, O. lyrata, Haemonchus contortus, Teladorsagia trifurcata, Trichostrongylus vitrinus, T. colubriformis, T. probolorus, T. capricola, Nematodirus spathiger, N. abnormalis, N. filicollis, N. helvetianus, Trichuris spp. and Skrjabinema ovis. Teladorsagia circumcincta was the most prevalent nematode in abomasum (52.6 %) followed by C. mentulatus (50 %). However, this latter nematode had the greater mean intensity and abundance. In the small intestine, T. colubriformis and T. vitrinus had the highest prevalence (36.4 %); the last one showed also the greater mean intensity and abundance. It should be emphasized the presence of Skrjabinema ovis (prevalence 39.1 %) in the large intestine, showing the greater mean abundance and intensity, although with a low values. Camelostrongylus mentulatus could be the most primitive nematode of the family trichostrongylidae recovered in this study; attending to its high prevalence, mean abundance and mean intensity, the possible specificity between this parasite and the Aoudad is discussed.

Moxidectin efficacy in a goat herd with chronic and generalized sarcoptic mange

A case of sarcoptic mange affecting almost all the animals of a dairy goat herd is described. This pruritic skin disease led progressively to high mortality and dramatic drop of milk yield. The lesions of the affected goats were typical of a chronic and generalized-diffuse sarcoptic mange. Diagnosis was confirmed by skin scrapings and histopathology in which many mites were demonstrated. All surviving goats were treated with injectable moxidectin solution 1% (CYDECTIN-Fort Dodge) at the dose of 0.2 mg/kg, applied every 15 days for four times, subcutaneously. Although pruritus had decreased soon after the first treatment, a satisfactory healing of cutaneous lesions was witnessed 6 weeks after the beginning of moxidectin trial. Parasitological cure was achieved in all affected animals by the end of the trial. In the four monthly followups, no evidence of sarcoptic mange could be found.

Arthropods of medicoveterinary importance in zoos

Zoos present a unique assemblage of arthropods, captive vertebrates, free-roaming wildlife, humans, and plants, each with its own biota of symbiotic organisms. Arthropods of medicoveterinary importance are well represented in zoos, and an ample literature documents their influence in these animal-rich environments. Mosquitoes are of greatest significance because of the animal and human pathogens they transmit, followed by ectoparasites, many of which are exotic and present health risks to captive and native animals. Biting flies, cockroaches, filth flies, and triatomid bugs represent additional concerns. Integrated management programs for arthropods in zoos are commonplace. Zoos can play a role in biosurveillance, serving as an advanced guard for detecting exotic arthropods and vector-borne diseases. We provide the first review of arthropods of medicoveterinary importance in zoos. A case is made for the value of collaborations between entomologists and zoo personnel as a means of enhancing research and public education while safeguarding the health of captive animals and the public.

Sarcoptic mange of gazelle (Gazella subguttarosa) and its medical importance in Iran

Sarcoptes scabiei infestation was diagnosed in four freshly dead and three net-captured gazelle while ranging freely. The captured animals presented with an alopecic pruritic skin disease with signs of crusted skin lesions, numerous small nodules which first appeared on the lips or nostrils and then it also extended towards the eyelids, around the ears, and, in some cases, over entire face, neck, trunk, and legs. Skin over the affected area gradually became bald, thick and hard, being dry and doughy to the touch, and serous fluid or sometimes blood oozes from the lesions which had a severe malodor. Skin scrapings confirmed the presence of the mite S. scabiei. Histopathology of lesions demonstrated marked acanthosis, hyperkeratosis, and parakeratosis. Microscopical examination also revealed all stages of S. scabiei, which were located mainly in the stratum corneum and also in the stratum granulosum. During the capture and sampling of the animals, four persons ranging in age from 25 to 62 years were exposed to scabies. Two relatives of one of them have been also affected by familiar contact. Clinical signs appeared within 9 days of exposure. They developed several pruretic erythematous papules with intense itching.

Oral ivermectin in scabies patients: a comparison with 1% topical lindane lotion

Scabies. which constitutes a significant proportion of the outpatient attendance in tropical dermatology clinics, has so far been treated with lindane, crotamiton, sulphur, permethrin, etc. Ivermectin, an orally administered drug, was tried in scabies patients and compared with 1% topical lindane lotion to evaluate its effects and toxicity profile. Two hundred scabies patients were randomly allocated to one of two groups. One group received oral invermectin in a single dose of 200 micrograms/kg body weight. The other received 1% lindane lotion for topical application overnight. Patients were assessed after 48 hours, two weeks and four weeks. After a period of four weeks, 82.6% of the patients in the ivermectin group showed marked improvement; only 44.44% of the patients in the lindance group showed a similar response. A side effects in the form of severe headache were noted in one patient in group A. Oral ivermectin is an easy drug to administer. It is given as a single oral dose, unlike lindane, which has to be applied topically. The compliance is accordingly increased. Moreover, ivermectin induces an early and effective improvement in signs and symptoms. Thus, it may be a better option for scabies than the traditional topical linlane lotion.

Current distribution of sarcoptic mange in wombats

OBJECTIVE

To determine the distribution and prevalence of sarcoptic mange in wombats, particularly the common wombat (Vombatus ursinus).

DESIGN

Questionnaire survey in two parts.

PROCEDURE

Questionnaires were distributed to biologists, rangers, animal carers and naturalists. Part 1 of the questionnaire aimed to determine the present distribution of sarcoptic mange in wombats (103 responses). Part 2 invited respondents to assess the prevalence of sarcoptic mange in wombats over a 3 month period (four responses). Information on wombats from 66 localities was received. Each locality represented an area of about 2500 km2.

RESULTS

Mange was observed at 93% of localities surveyed and Sarcoptes scabiei was present in common wombats at 52% of localities. Sarcoptic mange was highly prevalent (22%) in two common wombat populations in Victoria. Anecdotal evidence suggested that mange epizootics are sporadic, cause significant morbidity and mortality and have a substantial effect on local abundance. The respondents did not report sarcoptic mange in either northern hairy-nosed wombats (Lasiorhinus krefftii) or southern hairy-nosed wombats (Lasiorhinus latifrons).

CONCLUSIONS

Sarcoptic mange occurs in common wombat populations throughout the range of the common wombat including Tasmania and Flinders Island. While mange epizootics are sporadic, they have the potential to threaten the long-term survival of small, remnant populations.