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1.
Dis Aquat Organ ; 152: 61-71, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36394141

RESUMO

Despite being the most abundant sea turtle in the world, the olive ridley turtle Lepidochelys olivacea is classified as Vulnerable by the IUCN. There is evidence of congenital malformations in hatchlings, and the associated causes are multifactorial, with both genetic and environmental sources. Santuario Playa Ceuta (SPC) is a sanctuary for the olive ridley, located at the northernmost region of its nesting range in the Mexican Pacific. The objective of this study was to identify and quantify the prevalence and severity of congenital malformations in olive ridley embryos/hatchlings in SPC during the 2017 nesting season. We collected 62907 eggs from 643 relocated nests that were moved to a hatchery, of which 4242 eggs with obvious development did not hatch and were analyzed for this study. Hatching success was 53.9%, with 22.5% of nests (n = 145) and 0.54% of eggs (n = 344) showing embryos or hatchlings with malformations. The nest severity index was 2.4 (range: 1-10) malformed embryos or hatchlings per nest, and the organism severity index was 1.4 (range: 1-7) malformations per malformed embryo or hatchling. Leucism was the most prevalent malformation (34.4%; 170/494 total observed), with the craniofacial region showing the greatest diversity of malformations (17/35 types). Given the geographical position of SPC, extreme environmental conditions (e.g. cold, heat, and dryness) could be one of the main causes of teratogenesis in this species. However, more studies are needed regarding the presence of contaminants, genetic factors, health assessments of nesting females, and malformation rates of nests that remain in situ versus those that are relocated.


Assuntos
Tartarugas , Feminino , Animais , México/epidemiologia
2.
Ecol Evol ; 12(7): e9122, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35866022

RESUMO

Scavenging plays a vital role in maintaining ecosystem health and contributing to ecological functions; however, research in this sub-discipline of ecology is underutilized in developing and implementing wildlife conservation and management strategies. We provide an examination of the literature and recommend priorities for research where improved understanding of scavenging dynamics can facilitate the development and refinement of applied wildlife conservation and management strategies. Due to the application of scavenging research broadly within ecology, scavenging studies should be implemented for informing management decisions. In particular, a more direct link should be established between scavenging dynamics and applied management programs related to informing pharmaceutical delivery and population control through bait uptake for scavenging species, prevention of unintentional poisoning of nontarget scavenging species, the epidemiological role that scavenging species play in disease dynamics, estimating wildlife mortalities, nutrient transfer facilitated by scavenging activity, and conservation of imperiled facultative scavenging species. This commentary is intended to provide information on the paucity of data in scavenging research and present recommendations for further studies that can inform decisions in wildlife conservation and management. Additionally, we provide a framework for decision-making when determining how to apply scavenging ecology research for management practices and policies. Due to the implications that scavenging species have on ecosystem health, and their overall global decline as a result of anthropic activities, it is imperative to advance studies in the field of scavenging ecology that can inform applied conservation and management programs.

3.
Animals (Basel) ; 12(10)2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35625082

RESUMO

Fibropapillomatosis is a neoplastic disease of marine turtles, with green turtles (Chelonia mydas) being the most affected species. Fibropapillomatosis causes debilitating tumor growths on soft tissues and internal organs, often with lethal consequences. Disease incidence has been increasing in the last few decades and the reason is still uncertain. The potential viral infectious agent of Fibropapillomatosis, chelonid herpesvirus 5, has been co-evolving with its sea turtle host for millions of years and no major mutation linked with increased disease occurrence has been detected. Hence, frequent outbreaks in recent decades are likely attributable to external drivers such as large-scale anthropogenic changes in the green turtle coastal marine ecosystem. This study found that variations in sea surface temperature, salinity, and nutrient effluent discharge from nearby rivers were correlated with an increased incidence of the disease, substantiating that these may be among the significant environmental drivers impacting Fibropapillomatosis prevalence. This study offers data and insight on the need to establish a baseline of environmental factors which may drive Fibropapillomatosis and its clinical exacerbation. We highlight the multifactorial nature of this disease and support the inclusion of interdisciplinary work in future Fibropapillomatosis research efforts.

4.
Animals (Basel) ; 12(10)2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35625106

RESUMO

Wildlife dispersal directly influences population expansion patterns, and may have indirect effects on the spread of wildlife diseases. Despite its importance to conservation, little is known about dispersal for several species. Dispersal processes in expanding wolf (Canis lupus) populations in Europe is not well documented. Documenting the natural dispersal pattern of the expanding wolf population in the Alps might help understanding the overall population dynamics and identifying diseases that might be connected with the process. We documented 55 natural dispersal events of the expanding Italian wolf alpine population over a 20-year period through the use of non-invasive genetic sampling. We examined a 16-locus microsatellite DNA dataset of 2857 wolf samples mainly collected in the Western Alps. From this, we identified 915 individuals, recaptured 387 (42.3%) of individuals, documenting 55 dispersal events. On average, the minimum straight dispersal distance was 65.8 km (±67.7 km), from 7.7 km to 517.2 km. We discussed the potential implications for maintaining genetic diversity of the population and for wildlife diseases spreading.

5.
Biology (Basel) ; 11(5)2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35625395

RESUMO

Chronic wasting disease (CWD) is a contagious, fatal, neurodegenerative prion disease of cervids. The expanding geographical range and rising prevalence of CWD are increasing the risk of pathogen transfer and spillover of CWD to non-cervid sympatric species. As beavers have close contact with environmental and food sources of CWD infectivity, we hypothesized that they may be susceptible to CWD prions. We evaluated the susceptibility of beavers to prion diseases by challenging transgenic mice expressing beaver prion protein (tgBeaver) with five strains of CWD, four isolates of rodent-adapted prions and one strain of Creutzfeldt-Jakob disease. All CWD strains transmitted to the tgBeaver mice, with attack rates highest from moose CWD and the 116AG and H95+ strains of deer CWD. Mouse-, rat-, and especially hamster-adapted prions were also transmitted with complete attack rates and short incubation periods. We conclude that the beaver prion protein is an excellent substrate for sustaining prion replication and that beavers are at risk for CWD pathogen transfer and spillover.

6.
Conserv Physiol ; 10(1): coac018, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35492421

RESUMO

Inferring from patterns observed in biomedical research, ecoimmunological theory predicts that oxidative stress is a ubiquitous physiological cost that contributes to generating variation in immune function between individuals or species. This prediction is, however, often challenged by empirical studies testing the relationship between immune response or infection and oxidative status markers. This points out the importance of combining ecological immunology and oxidative stress ecology to further our understanding of the proximate causes and fitness consequences of individual variation in health, and adaptability to natural and anthropogenic environmental changes. I reviewed evidence and performed phylogenetic meta-analyses of changes in oxidative status markers owing to either injection of an antigen or infection in captive and free-living vertebrates (141 studies, 1262 effect sizes, 97 species). The dataset was dominated by studies on fish, birds and mammals, which provided 95.8% of effect sizes. Both antigen injection and parasite exposure were associated with changes of oxidative status. There were significant effects of taxonomic class and experimental environment (captivity vs. wild). In contrast with my predictions, age category (young vs. adult), study design (correlational vs. experimental) and proxies of pace of life (clutch size, litter size, and body mass; for birds and mammals only) were negligible in this dataset. Several methodological aspects (type of immunostimulant, laboratory assay, tissue analysed) showed significant effects on both strength and direction of effect. My results suggest that alterations of oxidative status are a widespread consequence of immune function across vertebrates. However, this work also identified heterogeneity in strength and direction of effect sizes, which suggests that immune function does not necessarily result in oxidative stress. Finally, this work identifies methodological caveats that might be relevant for the interpretation and comparability of results and for the application in conservation programs.

7.
Fungal Biol ; 126(1): 75-81, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34930560

RESUMO

Mycoviruses may influence the pathogenicity of disease-causing fungi. Although mycoviruses have been found in some chytrid fungi, limited testing has not detected them in Batrachochytrium dendrobatidis (Bd), the cause of the devastating amphibian disease, chytridiomycosis. Here we conducted a survey for mycovirus presence in 38 Bd isolates from Australia (n = 31), Brazil (n = 5) and South Korea (n = 2) with a combination of modern high-throughput sequencing and conventional dsRNA cellulose chromatography. Mycoviruses were not detected in any isolates. This result was unexpected, given the long evolutionary history of Bd, as well as the high prevalence of mycoviruses in related fungal species. Given our widespread sampling in Australia and the limited number of Bd introductions, we suggest that mycoviruses are uncommon or absent from Australian Bd. Testing more isolates from regions where Bd originated, as well as regions with high diversity or low fungal virulence may identify mycoviruses that could aid in disease control.


Assuntos
Quitridiomicetos , Micovírus , Anfíbios , Animais , Austrália , Batrachochytrium , Micovírus/genética
8.
Int J Parasitol Parasites Wildl ; 16: 83-94, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34466379

RESUMO

Feline immunodeficiency virus (FIV) is a pathogenic lentivirus related to human and simian immunodeficiency viruses that has been associated with AIDS-like pathologies in domestic and wild cats, as well as in hyenas. Despite known pathologies, progressive immunosuppression and ill health effects driven by these lentiviruses in association with other secondary infections remain understudied in free-ranging species. Here, the role of coinfections by gastrointestinal parasites and tick-borne hemoparasites for FIV disease progression was explored in 195 free-ranging African lions (Panthera leo) living in Kruger National Park (KNP), South Africa. Using statistical methodology, we evaluated the effects of FIV on a range of health indicators to explore how direct and indirect effects of FIV and associated coinfections align to determine lion health outcomes. Findings show direct negative effects of FIV on host immunity and nutritional status, and exacerbation of aggressive behaviors, conditions which may increase exposure/susceptibility to other secondary infections. When taken together, the contribution of coinfecting parasites to morbidity in lions is of similar magnitude as direct effects of FIV infection alone, suggesting that the particular coinfection assemblage may play a role in mediating disease progression within natural lion populations.

10.
Int J Parasitol Parasites Wildl ; 15: 262-269, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34277336

RESUMO

Wild animals are natural reservoir hosts for a variety of pathogens that can be transmitted to other wildlife, livestock, other domestic animals, and humans. Wild deer (family Cervidae) in Europe, Asia, and North and South America have been reported to be infected with gastrointestinal and vector-borne parasites. In Australia, wild deer populations have expanded considerably in recent years, yet there is little information regarding which pathogens are present and whether these pathogens pose biosecurity threats to humans, wildlife, livestock, or other domestic animals. To address this knowledge gap, PCR-based screening for five parasitic genera was conducted in blood samples (n = 243) sourced from chital deer (Axis axis), fallow deer (Dama dama), rusa deer (Rusa timorensis) and sambar deer (Rusa unicolor) sampled in eastern Australia. These blood samples were tested for the presence of DNA from Plasmodium spp., Trypanosoma spp., Babesia spp., Theileria spp. and Sarcocystis spp. Further, the presence of antibodies against Babesia bovis was investigated in serum samples (n = 105) by immunofluorescence. In this study, neither parasite DNA nor antibodies were detected for any of the five genera investigated. These results indicate that wild deer are not currently host reservoirs for Plasmodium, Trypanosoma, Babesia, Theileria or Sarcocystis parasites in eastern Australia. We conclude that in eastern Australia, wild deer do not currently play a significant role in the transmission of these parasites. This survey represents the first large-scale molecular study of its type in Australian wild deer and provides important baseline information about the parasitic infection status of these animals. The expanding populations of wild deer throughout Australia warrant similar surveys in other parts of the country and surveillance efforts to continually assess the level of threat wild deer could pose to humans, wildlife, livestock and other domestic animals.

11.
Dis Aquat Organ ; 144: 133-142, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33955851

RESUMO

Complex interactions among hosts, pathogens, and the environment affect the vulnerability of amphibians to the emergence of infectious diseases such as chytridiomycosis, caused by Batrachochytrium dendrobatidis (Bd). Boana curupi is a forest-dwelling amphibian endemic to the southern Atlantic Forest of South America, a severely fragmented region. Here, we evaluated whether abiotic factors (including air and water temperature, relative air humidity, and landscape) are correlated with chytrid infection intensity and prevalence in B. curupi. We found individuals infected with Bd in all populations sampled. Prevalence ranged from 25-86%, and the infection burden ranged from 1 to over 130000 zoospore genomic equivalents (g.e.) (mean ± SD: 4913 ± 18081 g.e.). The infection load differed among populations and was influenced by forest cover at scales of 100, 500, and 1000 m, with the highest infection rates recorded in areas with a higher proportion of forest cover. Our results suggest that the fungus is widely distributed in the populations of B. curupi in southern Brazil. Population and disease monitoring are necessary to better understand the relationships between host, pathogen, and environment, especially when, as in the case of B. curupi, threatened species are involved.


Assuntos
Quitridiomicetos , Micoses , Anfíbios , Animais , Anuros , Brasil/epidemiologia , Florestas , Micoses/epidemiologia , Micoses/veterinária
12.
Arq. bras. med. vet. zootec. (Online) ; 73(1): 203-206, Jan.-Feb. 2021. ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1153036

RESUMO

Teratoma is a rare neoplasia with differentiation in two or three germ cell lines. Intracranial teratoma in birds has rarely been reported, especially affecting the brain. This is the first report of a brain teratoma in a mallard with neurological clinical signs. The neoplasm was characterized as a mature brain teratoma, extending from the cerebellum to the brainstem, and with one nodule in the cortex.(AU)


O teratoma é uma neoplasia rara, com diferenciação em duas ou três linhagens de células germinativas. Teratomas intracranianos, em aves, são raramente relatados, principalmente, com localização cerebral. Este é o primeiro relato de teratoma cerebral em um pato-real com sinais clínicos neurológicos. A neoplasia foi caracterizada como um teratoma cerebral maduro, estendendo do cerebelo ao tronco encefálico e com um nódulo no córtex.(AU)


Assuntos
Animais , Teratoma/veterinária , Neoplasias Encefálicas/veterinária , Patos , Animais Selvagens
13.
Pesqui. vet. bras ; 41: e06832, 2021. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1250491

RESUMO

Amphisbenians are limbless reptiles that belong to the order Squamata. Due to their fossorial and secrevie habits, little is known about their morphology, ecology and pathological conditions that may affect them. In this manuscript, we present a brief guide for identification of normal structures as well as traumatic injuries on radiography and necropsy of Amphisbaena alba. From April to September 2019, three cases of A. alba with suspected trauma were referred to the Veterinary Hospital of the Federal University of Paraíba (UFPB). In the clinical evaluation, traumatic injuries were observed, and support therapy was instituted, but they did not resist and died shortly after. Bone fractures and organ ruptures, in addition to specific structures of this species were identified on radiography. A systematic necropsy was performed of all amphisbaenians in order to evaluate external and internal structures, not only to identify lesions but also to investigate the morphological aspects of amphisbenids. Macroscopically, multiple organ fractures and ruptures observed in radiographs were confirmed, in addition to the presence of the cestodes Semenoviella amphisbaenae in the large intestine. Histologically, it was possible to identify normal characteristics and microscopic lesions in the tissues. This is the first study to incorporate morphological, clinical, and pathological aspects of A. alba. This manuscript brings essential information for wildlife veterinarians and pathologists who may have to treat or perform a necropsy on these unique reptiles.(AU)


Anfisbenas são répteis desprovidos de membros que pertencem a ordem Squamata. Devido a seus hábitos fossoriais e reclusos, pouco se conhece sobre sua morfologia, ecologia e condições patológicas que possam afetá-las. Neste artigo, um guia sucinto para a necropsia, identificação de tecidos e órgãos e lesões encontradas em Amphisbaena alba, é apresentado. Durante março e dezembro de 2019, três casos de A. alba com suspeita de trauma foram encaminhados ao Hospital Veterinário da Universidade Federal da Paraíba. Na avaliação clínica foram observadas lesões traumáticas e instituído um suporte terapêutico, porém não resistiram e morreram em seguida. Foram realizadas projeções radiográficas onde identificaram fraturas e ruptura de órgãos, além de identificar estruturas específicas dessa espécie. Uma avaliação completa de estruturas externas e internas foi conduzida para investigar aspectos morfológicos dos anfisbenídeos. Macroscopicamente foram confirmadas múltiplas fraturas e rupturas de órgãos observadas anteriormente nas radiografias, além disso evidenciou no intestino grosso presença de parasitos anoplocéfalos denominados Semenoviella amphisbaenae. Na histologia foi possível identificar características normais e lesões microscópicas nos tecidos. Esse é o primeiro estudo a incorporar aspectos morfológicos, clínicos e patológicos de A. alba. Esse manuscrito traz informações essenciais para clínicos e patologistas de animais selvagens que podem se deparar com casos clínicos ou de necropsia de Amphisbaena alba.(AU)


Assuntos
Animais , Répteis/lesões , Autopsia/veterinária , Ferimentos e Lesões , Radiografia , Técnicas e Procedimentos Diagnósticos/mortalidade , Animais Selvagens
14.
Pesqui. vet. bras ; 41: e06832, 2021. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-32483

RESUMO

Amphisbenians are limbless reptiles that belong to the order Squamata. Due to their fossorial and secrevie habits, little is known about their morphology, ecology and pathological conditions that may affect them. In this manuscript, we present a brief guide for identification of normal structures as well as traumatic injuries on radiography and necropsy of Amphisbaena alba. From April to September 2019, three cases of A. alba with suspected trauma were referred to the Veterinary Hospital of the Federal University of Paraíba (UFPB). In the clinical evaluation, traumatic injuries were observed, and support therapy was instituted, but they did not resist and died shortly after. Bone fractures and organ ruptures, in addition to specific structures of this species were identified on radiography. A systematic necropsy was performed of all amphisbaenians in order to evaluate external and internal structures, not only to identify lesions but also to investigate the morphological aspects of amphisbenids. Macroscopically, multiple organ fractures and ruptures observed in radiographs were confirmed, in addition to the presence of the cestodes Semenoviella amphisbaenae in the large intestine. Histologically, it was possible to identify normal characteristics and microscopic lesions in the tissues. This is the first study to incorporate morphological, clinical, and pathological aspects of A. alba. This manuscript brings essential information for wildlife veterinarians and pathologists who may have to treat or perform a necropsy on these unique reptiles.(AU)


Anfisbenas são répteis desprovidos de membros que pertencem a ordem Squamata. Devido a seus hábitos fossoriais e reclusos, pouco se conhece sobre sua morfologia, ecologia e condições patológicas que possam afetá-las. Neste artigo, um guia sucinto para a necropsia, identificação de tecidos e órgãos e lesões encontradas em Amphisbaena alba, é apresentado. Durante março e dezembro de 2019, três casos de A. alba com suspeita de trauma foram encaminhados ao Hospital Veterinário da Universidade Federal da Paraíba. Na avaliação clínica foram observadas lesões traumáticas e instituído um suporte terapêutico, porém não resistiram e morreram em seguida. Foram realizadas projeções radiográficas onde identificaram fraturas e ruptura de órgãos, além de identificar estruturas específicas dessa espécie. Uma avaliação completa de estruturas externas e internas foi conduzida para investigar aspectos morfológicos dos anfisbenídeos. Macroscopicamente foram confirmadas múltiplas fraturas e rupturas de órgãos observadas anteriormente nas radiografias, além disso evidenciou no intestino grosso presença de parasitos anoplocéfalos denominados Semenoviella amphisbaenae. Na histologia foi possível identificar características normais e lesões microscópicas nos tecidos. Esse é o primeiro estudo a incorporar aspectos morfológicos, clínicos e patológicos de A. alba. Esse manuscrito traz informações essenciais para clínicos e patologistas de animais selvagens que podem se deparar com casos clínicos ou de necropsia de Amphisbaena alba.(AU)


Assuntos
Animais , Répteis/lesões , Autopsia/veterinária , Ferimentos e Lesões , Radiografia , Técnicas e Procedimentos Diagnósticos/mortalidade , Animais Selvagens
15.
Parasit Vectors ; 13(1): 471, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32933573

RESUMO

This letter comments on the article "The treatment of sarcoptic mange in wildlife: a systematic review" published in Parasites & Vectors 2019, 12:99, and discusses the limitations in the use of endectocides for scabies control in free-ranging wildlife. The ecological impact and drug resistance to ivermectin are also discussed. In our view, scabies control in free-ranging wildlife should be based preferably on population management measures, and whether to apply individual treatments to free-ranging populations should be considered very carefully and avoided where not absolutely warranted.


Assuntos
Acaricidas/uso terapêutico , Animais Selvagens/parasitologia , Escabiose/veterinária , Animais , Resíduos de Drogas/análise , Resistência a Medicamentos , Contaminação de Alimentos/análise , Humanos , Carne/análise , Sarcoptes scabiei/efeitos dos fármacos , Sarcoptes scabiei/fisiologia , Escabiose/tratamento farmacológico , Escabiose/parasitologia
16.
Viruses ; 12(8)2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32796534

RESUMO

Gammaherpesvirus infections have been described in cervids worldwide, mainly the genera Macavirus or Rhadinovirus. However, little is known about the gammaherpesviruses species infecting cervids in Norway and Fennoscandia. Blood samples from semi-domesticated (n = 39) and wild (n = 35) Eurasian tundra reindeer (Rangifer tarandus tarandus), moose (Alces alces, n = 51), and red deer (Cervus elaphus, n = 41) were tested using a panherpesvirus DNA polymerase (DPOL) PCR. DPOL-PCR-positive samples were subsequently tested for the presence of glycoprotein B (gB) gene. The viral DPOL gene was amplified in 28.2% (11/39) of the semi-domesticated reindeer and in 48.6% (17/35) of the wild reindeer. All moose and red deer tested negative. Additionally, gB gene was amplified in 4 of 11 semi-domesticated and 15 of 17 wild Eurasian reindeer DPOL-PCR-positive samples. All the obtained DPOL and gB sequences were highly similar among them, and corresponded to a novel gammaherpesvirus species, tentatively named Rangiferine gammaherpesvirus 1, that seemed to belong to a genus different from Macavirus and Rhadinovirus. This is the first report of a likely host-specific gammaherpesvirus in semi-domesticated reindeer, an economic and cultural important animal, and in wild tundra reindeer, the lastpopulation in Europe. Future studies are required to clarify the potential impact of this gammaherpesvirus on reindeer health.


Assuntos
Animais Domésticos/virologia , Gammaherpesvirinae/classificação , Infecções por Herpesviridae/veterinária , Rena/virologia , Animais , Animais Selvagens/virologia , Gammaherpesvirinae/isolamento & purificação , Infecções por Herpesviridae/sangue , Noruega , Filogenia
17.
Ecol Modell ; 4172020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32189826

RESUMO

Epidemiological surveillance for important wildlife diseases often relies on samples obtained from hunter-harvested animals. A problem, however, is that although convenient and cost-effective, hunter-harvest samples are not representative of the population due to heterogeneities in disease distribution and biased sampling. We developed an agent-based modeling framework that i) simulates a deer population in a user-generated landscape, and ii) uses a snapshot of the in silico deer population to simulate disease prevalence and distribution, harvest effort and sampling as per user-specified parameters. This framework can incorporate real-world heterogeneities in disease distribution, hunter harvest and harvest-based sampling, and therefore can be useful in informing wildlife disease surveillance strategies, specifically to determine population-specific sample sizes necessary for prompt detection of disease. Application of this framework is illustrated using the example of chronic wasting disease (CWD) surveillance in Missouri's white-tailed deer (Odocoileus virginianus) population. We show how confidence in detecting CWD is grossly overestimated under the unrealistic, but standard, assumptions that sampling effort and disease are randomly and independently distributed. We then provide adjusted sample size recommendations based on more realistic assumptions. Wildlife agencies can use these open-access models to design their CWD surveillance. Furthermore, these models can be readily adapted to other regions and other wildlife disease systems.

18.
Ecol Lett ; 22(10): 1709-1722, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31321874

RESUMO

Immunosenescence, the decline in immune defense with age, is an important mortality source in elderly humans but little is known of immunosenescence in wild animals. We systematically reviewed and meta-analysed evidence for age-related changes in immunity in captive and free-living populations of wild species (321 effect sizes in 62 studies across 44 species of mammals, birds and reptiles). As in humans, senescence was more evident in adaptive (acquired) than innate immune functions. Declines were evident for cell function (antibody response), the relative abundance of naïve immune cells and an in vivo measure of overall immune responsiveness (local response to phytohaemagglutinin injection). Inflammatory markers increased with age, similar to chronic inflammation associated with human immunosenescence. Comparisons across taxa and captive vs free-living animals were difficult due to lack of overlap in parameters and species measured. Most studies are cross-sectional, which yields biased estimates of age-effects when immune function co-varies with survival. We therefore suggest longitudinal sampling approaches, and highlight techniques from human cohort studies that can be incorporated into ecological research. We also identify avenues to address predictions from evolutionary theory and the contribution of immunosenescence to age-related increases in disease susceptibility and mortality.


Assuntos
Aves/fisiologia , Imunossenescência , Mamíferos/fisiologia , Répteis/fisiologia , Envelhecimento , Animais , Estudos Transversais , Inflamação
19.
Exp Appl Acarol ; 78(4): 547-554, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31289968

RESUMO

Demodicosis is most frequently observed in the domestic dog (Canis familiaris), but it has rarely been reported in bats (Chiroptera). The overpopulation of Demodex spp. that causes dermatological changes is generally associated with a compromised immune system. We describe the gross and histological features of generalized demodicosis in an adult female African straw-coloured fruit bat (Eidolon helvum) drawn from a captive research colony. The histology of the lesions revealed comedones and follicular infundubular cysts harbouring numerous Demodex spp. mites, eliciting a minimal inflammatory response in the adjacent dermis. The histological examination of a full set of tissues did not reveal clear evidence of immunosuppression, although a clinical history of recent abortion and possible stressors due to captivity could be considered risk factors for the demodicosis. Attempts to determine the Demodex species using PCR on DNA extracted from the formalin fixed paraffin embedded tissue failed. This is the first clinical and histological description of demodicosis in Eidolon helvum.


Assuntos
Quirópteros , Infestações por Ácaros/veterinária , Ácaros/fisiologia , Animais , Animais de Zoológico/fisiologia , Diagnóstico Diferencial , Feminino , Gana , Infestações por Ácaros/diagnóstico , Infestações por Ácaros/parasitologia , Infestações por Ácaros/patologia
20.
Int J Parasitol Parasites Wildl ; 8: 88-93, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30723669

RESUMO

Malarial and other haemosporidian parasites are widespread; however, their temporal dynamics are ill-understood. Longitudinal sampling of a threatened riparian bird revealed a consistently very low prevalence over 13 years (∼5%) despite infections persisting and prevalence increasing with age. In contrast, three key species within this tropical community were highly infected (∼20-75% prevalence) and these differences were stable. Although we found novel lineages and phylogenetic structure at the local level, there was little geographic structuring within Australasia. This study suggests that malarial parasite susceptibility is determined by host factors and that species can maintain low levels despite high community prevalence.

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