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1.
Evol Appl ; 11(2): 123-139, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29387150

RESUMO

Restoration of lost species ranges to their native distribution is key for the survival of endangered species. However, reintroductions often fail and long-term genetic consequences are poorly understood. Alpine ibex (Capra ibex) are wild goats that recovered from <100 individuals to ~50,000 within a century by population reintroductions. We analyzed the population genomic consequences of the Alpine ibex reintroduction strategy. We genotyped 101,822 genomewide single nucleotide polymorphism loci in 173 Alpine ibex, the closely related Iberian ibex (Capra pyrenaica) and domestic goat (Capra hircus). The source population of all Alpine ibex maintained genetic diversity comparable to Iberian ibex, which experienced less severe bottlenecks. All reintroduced Alpine ibex populations had individually and combined lower levels of genetic diversity than the source population. The reintroduction strategy consisted of primary reintroductions from captive breeding and secondary reintroductions from established populations. This stepwise reintroduction strategy left a strong genomic footprint of population differentiation, which increased with subsequent rounds of reintroductions. Furthermore, analyses of genomewide runs of homozygosity showed recent inbreeding primarily in individuals of reintroduced populations. We showed that despite the rapid census recovery, Alpine ibex carry a persistent genomic signature of their reintroduction history. We discuss how genomic monitoring can serve as an early indicator of inbreeding.

2.
Exp Appl Acarol ; 72(3): 277-289, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28593481

RESUMO

Coxiella burnetii is the causative agent of Q fever, a zoonotic disease of public health importance. The role of wildlife and their ticks in the epidemiology of C. burnetii in Kenya is unknown. This study analysed the occurrence and prevalence of the pathogen in wildlife and their ticks at two unique wildlife-livestock interfaces of Laikipia and Maasai Mara National Reserve (MMNR) with the aim to determine the potential risk of transmission to livestock and humans. Blood from 79 and 73 animals in Laikipia and MMNR, respectively, and 756 and 95 ixodid ticks in each of the areas, respectively, was analysed. Ticks were pooled before analyses into 137 and 29 samples in Laikipia and MMNR, respectively, of one to eight non-engorged ticks according to species and animal host. Real-time PCR amplifying the repetitive insertion element IS1111a of the transposase gene was used to detect C. burnetii DNA. Although none of the animals and ticks from MMNR tested positive, ticks from Laikipia had an overall pooled prevalence of 2.92% resulting in a maximum-likelihood estimate of prevalence of 0.54%, 95% CI 0.17-1.24. Ticks positive for C. burnetii DNA belonged to the genus Rhipicephalus at a pooled prevalence of 2.96% (maximum-likelihood estimate of prevalence of 0.54%, 95% CI 0.17-1.26). These ticks were Rhipicephalus appendiculatus, R. pulchellus and R. evertsi at pooled prevalence of 3.77, 3.03 and 2.04%, respectively. The presence of C. burnetii in ticks suggests circulation of the pathogen in Laikipia and demonstrates they may play a potential role in the epidemiology of Q fever in this ecosystem. The findings warrant further studies to understand the presence of C. burnetii in domestic animals and their ticks within both study areas.


Assuntos
Coxiella burnetii/isolamento & purificação , Febre Q/veterinária , Carrapatos/microbiologia , Animais , Animais Selvagens/microbiologia , Animais Selvagens/parasitologia , Coxiella burnetii/genética , Humanos , Quênia/epidemiologia , Funções Verossimilhança , Gado/microbiologia , Gado/parasitologia , Febre Q/epidemiologia , Febre Q/transmissão , Inquéritos e Questionários , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterinária
3.
PLoS One ; 12(1): e0170827, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28135293

RESUMO

BACKGROUND: Genetic differentiation in historically connected populations could be the result of genetic drift or adaptation, two processes that imply a need for differing strategies in population management. The aim of our study was to use neutral genetic markers to characterize C. pyrenaica populations genetically and examine results in terms of (i) demographic history, (ii) subspecific classification and (iii) the implications for the management of Iberian ibex. METHODOLOGY/PRINCIPAL FINDINGS: We used 30 neutral microsatellite markers from 333 Iberian ibex to explore genetic diversity in the three main Iberian ibex populations in Spain corresponding to the two persisting subspecies (victoria and hispanica). Our molecular analyses detected recent genetic bottlenecks in all the studied populations, a finding that coincides with the documented demographic decline in C. pyrenaica in recent decades. Genetic divergence between the two C. pyrenaica subspecies (hispanica and victoriae) was substantial (FST between 0.39 and 0.47). Unexpectedly, we found similarly high genetic differentiation between two populations (Sierra Nevada and Maestrazgo) belonging to the subspecies hispanica. The genetic pattern identified in our study could be the result of strong genetic drift due to the severe genetic bottlenecks in the studied populations, caused in turn by the progressive destruction of natural habitat, disease epidemics and/or uncontrolled hunting. CONCLUSIONS: Previous Capra pyrenaica conservation decision-making was based on the clear distinction between the two subspecies (victoriae and hispanica); yet our paper raises questions about the usefulness for conservation plans of the distinction between these subspecies.


Assuntos
Variação Genética , Cabras/genética , Alelos , Animais , Análise por Conglomerados , Genética Populacional , Geografia , Heterozigoto , Filogenia , Densidade Demográfica , Software , Espanha
4.
Parasit Vectors ; 9(1): 521, 2016 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-27682456

RESUMO

BACKGROUND: Filarioid nematode parasites are major health hazards with important medical, veterinary and economic implications. Recently, they have been considered as indicators of climate change. FINDINGS: In this paper, we report the first record of Setaria tundra in roe deer from the Iberian Peninsula. Adult S. tundra were collected from the peritoneal cavity during the post-mortem examination of a 2 year-old male roe deer, which belonged to a private fenced estate in La Alcarria (Guadalajara, Spain). Since 2012, the area has suffered a high roe deer decline rate (75 %), for unknown reasons. Aiming to support the morphological identification and to determine the phylogenetic position of S. tundra recovered from the roe deer, a fragment of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene from the two morphologically identified parasites was amplified, sequenced and compared with corresponding sequences of other filarioid nematode species. Phylogenetic analyses revealed that the isolate of S. tundra recovered was basal to all other formely reported Setaria tundra sequences. The presence of all other haplotypes in Northern Europe may be indicative of a South to North outbreak in Europe. CONCLUSIONS: This is the first report of S. tundra in roe deer from the Iberian Peninsula, with interesting phylogenetic results, which may have further implications in the epidemiological and genetic studies of these filarioid parasites. More studies are needed to explore the reasons and dynamics behind the rapid host/geographic expansion of the filarioid parasites in Europe.

5.
Ecohealth ; 13(4): 708-719, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27554373

RESUMO

Very little is known about the influence of massive and long distance migration on parasite epidemiology. Migration can simultaneously minimize exposure to common parasites in their habitats and increase exposure to novel pathogens from new environments and habitats encountered during migration, while physiological stress during long distance movement can lead to immune suppression, which makes migrants vulnerable to parasites. In this paper, we investigated the diversity, prevalence, parasite load, co-infection patterns and predilection sites of adult gastrointestinal helminths in 130 migrating wildebeests and tested for their relation with animal age, sex and migration time (which also could indicate different migration routes), and compared them with the non-migratory wildebeest. Surprisingly, only four parasite species were found, Oesophagostomum columbianum, Haemonchus placei, Calicophoron raja and Moniezia expansa, which were lower than in non-migratory wildebeest reported in the literature. These parasites were generalists, infecting livestock, and suggests that wildebeest and livestock, because of their interaction during migration, have a cross-infection risk. There was a negative relation between parasites diversity, prevalence and intensity of infection, and host age, which suggests that wildebeests acquire protective immunity against these parasites as they get older. Prevalence and intensity of infection were higher among wildebeest crossing the Mara Bridge (early migrants) compared to those crossing the Serena (late migrants), which suggests that early migrants (or migrants originating from different areas) have varying infection intensities. The prevalence and intensity of infection were higher in males compared to females and may be due to ecological, behavioural, or physiological differences between males and females. Our findings compared to those of previous studies suggest that migration may provide a mechanism to minimize exposure of hosts to common parasites through migratory escape, but this result awaits examination of helminths epidemiology of non-migratory wildebeests from areas of migrant origins. The potential parasitic cross-infection between wildebeests and livestock is a real risk to be taken into account in the management of wildebeest migration corridors.


Assuntos
Migração Animal , Ruminantes/parasitologia , Animais , Ecossistema , Feminino , Helmintos , Masculino , Parasitos
6.
Parasit Vectors ; 9(1): 402, 2016 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-27435176

RESUMO

Although neglected, the mite Sarcoptes scabiei is an unpredictable emerging parasite, threatening human and animal health globally. In this paper we report the first fatal outbreak of sarcoptic mange in the endangered Himalayan lynx (Lynx lynx isabellinus) from Pakistan. A 10-year-old male Himalayan lynx was found in a miserable condition with severe crusted lesions in Chitral District, and immediately died. Post-mortem examination determined high S. scabiei density (1309 mites/cm(2) skin). It is most probably a genuine emergence, resulting from a new incidence due to the host-taxon derived or prey-to-predator cross-infestation hypotheses, and less probable to be apparent emergence resulting from increased infection in the Himalayan lynx population. This is an alarming situation for the conservation of this already threatened population, which demands surveillance for early detection and eventually rescue and treatment of the affected Himalayan lynx.


Assuntos
Surtos de Doenças , Lynx , Sarcoptes scabiei/patogenicidade , Escabiose/veterinária , Animais , Paquistão/epidemiologia , Escabiose/epidemiologia
7.
J Wildl Dis ; 52(3): 599-608, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27224210

RESUMO

Following mass deaths of Laughing Doves (Streptopelia senegalensis) in different localities throughout Kenya, internal organs obtained during necropsy of two moribund birds were sampled and analyzed by next generation sequencing. We isolated the virulent strain of pigeon paramyxovirus type-1 (PPMV-1), PPMV1/Laughing Dove/Kenya/Isiolo/B2/2012, which had a characteristic fusion gene motif (110)GGRRQKRF(117). We obtained a partial full genome of 15,114 nucleotides. The phylogenetic relationship based on the fusion gene and genomic sequence grouped our isolate as class II genotype VI, a group of viruses commonly isolated from wild birds but potentially lethal to Chickens ( Gallus gallus domesticus ). The fusion gene isolate clustered with PPMV-I strains from pigeons (Columbidae) in Nigeria. The complete genome showed a basal and highly divergent lineage to American, European, and Asian strains, indicating a divergent evolutionary pathway. The isolated strain is highly virulent and apparently species-specific to Laughing Doves in Kenya. Risk of transmission of such a strain to poultry is potentially high whereas the cyclic epizootic in doves is a threat to conservation of wild Columbidae in Kenya.


Assuntos
Columbidae/virologia , Sequenciamento de Nucleotídeos em Larga Escala , Vírus da Doença de Newcastle/genética , Filogenia , Animais , Galinhas , Genômica , Quênia , Doença de Newcastle
8.
Int J Vet Sci Med ; 4(2): 27-32, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30255036

RESUMO

The use of biopsy darts for remote collection of tissue samples from free-ranging terrestrial and aquatic animal species has gained popularity in the recent past. The success of darting is very important since scientists may not have many chances to re-dart the same animal, especially with the free-ranging elusive wildlife species. We used wildebeest (Connochaetes taurinus) as a model to estimate the optimum shooting distance, pressure and the shot part of the body through which a researcher can optimize the success and amount of tissue collected from similar wild land mammalian species. Wildebeests were darted at six categories of distances ranging between 10 and 45 m and dart gun pressures of 5-14 millibar. The number of failed darts increased by increasing the darting distance: 0% (10 m), 0% (20 m), 6% (30 m), 20% (35 m), 71% (40 m), and 67% (45 m). There was a notable effect of the distances on the amount of tissue collected 20 m offered the best results. Dart gun pressure had no effect on the amount of tissue samples obtained. The amount of tissue obtained from successful darts was the same whether the animal was darted on the shoulder or thigh. In this paper, we present a practical guideline for remote biopsy darting of wildebeest to obtain optimum amount of tissue samples, which could be generalized for similar wild land mammalian species.

10.
Parasit Vectors ; 8: 587, 2015 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-26568063

RESUMO

BACKGROUND: The mite Sarcoptes scabiei has a known host-range of over 100 mammal species including humans. One of the prime objectives of the Sarcoptes-World Molecular Network (WMN) is to design and develop universal Sarcoptes PCR-based diagnosis methods. METHODS: We describe here for the first time two universal mitochondrial-based diagnosis methods: (i) conventional end-point PCR and (ii) TaqMan real-time PCR. The design of both of these universal diagnosis methods was based on Sarcoptes samples collected from 23 host species in 14 countries. RESULTS: These methods, based on skin scrapings, were successfully used to etiologically confirm the diagnosis of different clinical degrees of sarcoptic mange in 48 animals belonging to six species. These universal PCR-based diagnosis methods are highly specific, technically sensitive and simple, and are based on the amplification of 135 bp from the Mitochondrial 16S rDNA. The method based on TaqMan real-time qPCR was more sensitive than the conventional end-point PCR. CONCLUSIONS: Two universal PCR-based diagnosis methods for S. scabiei were successfully designed and applied; one based on conventional end-point PCR and the other on TaqMan real-time PCR. We recommend further testing and the application of these new universal methods worldwide.


Assuntos
Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase/métodos , Sarcoptes scabiei/genética , Escabiose/diagnóstico , Animais , Primers do DNA/genética , DNA Mitocondrial/genética , DNA Ribossômico/genética , Humanos , RNA Ribossômico 16S/genética
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