RESUMEN
Large populations of unowned cats constitute an animal welfare, ecological, societal and public health issue worldwide. Their relocation and homing are currently carried out in many parts of the world with the intention of relieving suffering and social problems, while contributing to ethical and humane population control in these cat populations. An understanding of an individual cat's lifestyle and disease status by veterinary team professionals and those working with cat charities can help to prevent severe cat stress and the spread of feline pathogens, especially vector-borne pathogens, which can be overlooked in cats. In this article, we discuss the issue of relocation and homing of unowned cats from a global perspective. We also review zoonotic and non-zoonotic infectious agents of cats and give a list of practical recommendations for veterinary team professionals dealing with homing cats. Finally, we present a consensus statement consolidated at the 15th Symposium of the Companion Vector-Borne Diseases (CVBD) World Forum in 2020, ultimately to help veterinary team professionals understand the problem and the role they have in helping to prevent and manage vector-borne and other pathogens in relocated cats.
Asunto(s)
Enfermedades de los Gatos , Vectores de Enfermedades , Gatos , Animales , Bienestar del Animal , Enfermedades de los Gatos/prevención & controlRESUMEN
Reports in the literature indicate that species of Hepatozoon commonly occur in African wild dog (AWD) or painted wolf (Lycaon pictus) populations. These findings were based on examination of blood smears by microscopy, and specific identity of the Hepatozoon sp. gamonts seen could not be confirmed. We present the first in-depth molecular data on the prevalence of species of Hepatozoon in a free-ranging AWD population. In a general health survey of AWDs in the Kruger National Park, blood specimens (n = 74) collected from 54 individuals were examined for the presence of Hepatozoon spp. At first sampling, specimens from 42 of 54 individuals (77.7%) were positive, based on the primer set HepF300 and HepR900. Twenty individuals were resampled between 51 and 69 days after first sampling; one of these was resampled twice. Samples from six individuals that had tested negative previously now reacted positive. Assuming that all 54 individuals were still alive, the prevalence had therefore increased to 48 individuals infected, or 88.8%. Resultant 18S rDNA sequences isolated from these specimens share high similarity to other Hepatozoon canis genotypes. Phylogenetic analysis recovered the Hepatozoon sp. isolated from AWDs within the H. canis cluster, which includes species of Hepatozoon from other canid and tick hosts.
RESUMEN
In sub-Saharan Africa, babesiosis in domestic dogs is caused primarily by Babesia rossi. Black-backed jackals (Canis mesomelas), which are subclinical carriers of B. rossi, were a likely reservoir host from which infection passed to domestic dogs. The role of other indigenous canids, e.g. African wild dogs (Lycaon pictus), as reservoirs of B. rossi has not been elucidated. The question also arises whether genetic differences have arisen between B. rossi infecting domestic dogs and "ancestral" B. rossi in jackals. In a previous study we found that nearly one-third (27 of 91) of jackals were infected with B. rossi; this was confirmed by 18S rDNA sequence analysis. In this study, the near full-length B. rossi 18S rRNA gene was successfully amplified from 6 domestic dogs and 3 black-backed jackals. The obtained recombinant sequences were identical (100 %) to previously described B. rossi sequences of black-backed jackals in South Africa, and 99 % similar to B. rossi from dogs in South Africa and the Sudan. Although blood specimens from 5 (10 %) of 52 free-ranging African wild dogs (from Kruger National Park, South Africa, reacted with the B. rossi probe on RLB hybridisation, the presence of B. rossi could not be confirmed by amplification and sequencing, nor by multiplex, real-time PCR. Although African wild dogs they can be infected with B. rossi without showing clinical signs, our findings suggest that they are apparently not important reservoir hosts of B. rossi.
Asunto(s)
Babesiosis/epidemiología , Canidae/parasitología , Especificidad del Huésped , Animales , Babesia/genética , Babesiosis/parasitología , Enfermedades de los Perros/parasitología , Perros , Chacales/parasitología , Reacción en Cadena de la Polimerasa , Sudáfrica/epidemiologíaRESUMEN
The two black rhinoceros subspecies (Diceros bicornis bicornis and D. b. minor) in South African conservation areas are managed as separate metapopulations. Since infection with Babesia bicornis can be fatal in black rhinoceroses, occurrence of this and other piroplasms in the two metapopulations was determined to assess possible risk. Blood specimens were collected from 156 black rhinoceroses: 80 from D. b. bicornis and 76 from D. b. minor. DNA was extracted; the V4 hypervariable region of the parasite 18S rRNA gene was amplified and subjected to the Reverse Line Blot (RLB) hybridization assay. There was a significant difference in occurrence of piroplasms: 18/80 (23%) in D. b. bicornis and 39/76 (51%) in D. b. minor. Theileria bicornis occurred in significantly more of the D. b. minor population (36/76; 47%) than the D. b. bicornis population (1/80; 1%); with B. bicornis the difference was not significant: D. b. bicornis 5/80 (6%) and D. b. minor 9/76 (11%). Three individuals were infected with Theileria equi. Results were confirmed using molecular characterization of the near full-length parasite 18S rRNA gene of 13 selected specimens. We identified four (Tb1, Tb2, Tb3 and Tb4) 18S rDNA sequence types for T. bicornis, two for B. bicornis (Bb1 and Bb2) and one for T. equi (Teq1). We furthermore identified T. bicornis haplotypes H1, H3 and H4 in 10 rhinoceroses; H3 was the most common haplotype identified. Rhinoceroses inhabiting more arid areas are apparently free of T. bicornis and B. bicornis, probably due to the absence or scarcity of vectors. When individuals are relocated for metapopulation management purposes, appropriate prophylactic action should be taken to minimise the risk of babesiosis, which could be fatal.
Asunto(s)
Babesia/aislamiento & purificación , Babesiosis/epidemiología , Conservación de los Recursos Naturales , Perisodáctilos , Theileria/aislamiento & purificación , Theileriosis/epidemiología , Animales , Babesiosis/parasitología , Secuencia de Bases , ADN Ribosómico/análisis , Interacciones Huésped-Parásitos , Filogenia , Prevalencia , ARN Ribosómico 18S/análisis , Sudáfrica/epidemiología , Especificidad de la Especie , Theileriosis/parasitologíaRESUMEN
The Companion Vector-Borne Diseases (CVBD) World Forum is a working group of leading international experts who meet annually to evaluate current scientific findings and future trends concerning the distribution, pathogenesis, clinical presentation, diagnosis and prevention of vector-borne infections of dogs and cats. At the 14th Symposium of the CVBD World Forum in Trieste, Italy (March 25-28, 2019), we identified the need to (i) bring attention to the potential spread of parasites and vectors with relocated dogs, and (ii) provide advice to the veterinary profession regarding the importance of surveillance and treatment for parasites and vector-borne infections when rehoming dogs. This letter shares a consensus statement from the CVBD World Forum as well as a summary of the problem faced, including the role of veterinary professionals in parasite surveillance, causal issues, and the importance of interdisciplinary cooperation in addressing the problem. To limit opportunities for dissemination of parasites and vectors, whenever possible, underlying problems creating the need for dog rehoming should be addressed. However, when it is necessary to rehome dogs, this should ideally take place in the country and national region of origin. When geographically distant relocation occurs, veterinary professionals have a vital role to play in public education, vigilance for detection of exotic vectors and infections, and alerting the medical community to the risk(s) for pathogen spread. With appropriate veterinary intervention, dog welfare needs can be met without inadvertently allowing global spread of parasites and their vectors.
Asunto(s)
Enfermedades de los Perros/parasitología , Enfermedades de los Perros/transmisión , Enfermedades Transmitidas por Vectores/prevención & control , Bienestar del Animal , Animales , Congresos como Asunto , Consenso , Vectores de Enfermedades , Enfermedades de los Perros/epidemiología , Perros , Internacionalidad , Italia , Enfermedades Transmitidas por Vectores/epidemiología , Enfermedades Transmitidas por Vectores/parasitología , VeterinariosRESUMEN
No abstract available.
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Fundaciones/estadística & datos numéricos , Parasitología/organización & administración , Medicina Veterinaria/organización & administración , Administración Financiera/estadística & datos numéricos , Parasitología/estadística & datos numéricos , Sociedades Médicas/organización & administración , Sociedades Médicas/estadística & datos numéricos , Sudáfrica , Medicina Veterinaria/estadística & datos numéricosRESUMEN
The Tropical Council for Companion Animal Parasites Ltd. (TroCCAP) is a not-for-profit organisation whose mission is to independently inform, guide and make best-practice recommendations for the diagnosis, treatment and control of companion animal parasites in the tropics and sub-tropics, with the aim of protecting animal and human health. In line with this primary mission, TroCCAP recently developed guidelines for the diagnosis, treatment and control of feline and canine parasites in the tropics. The development of these guidelines required unique and complex considerations to be addressed, often inapplicable to developed nations. Much of the tropics encompass middle-to-low income countries in which poor standards of environmental hygiene and large populations of stray dogs and cats coexist. In these regions, a range of parasites pose a high risk to companion animals, which ultimately may place their owners at risk of acquiring parasitic zoonoses. These considerations led to the development of unique recommendations with regard, for example, to deworming and endoparasite testing intervals for the control of both global and 'region-specific' parasites in the tropics. Moreover, the 'off-' or 'extra'-label use of drugs for the treatment and control of parasitic infections is common practice in many tropical countries and many generic products lack manufacturers' information on efficacy, safety, and quality control. Recommendations and advice concerning the use of such drugs and protocols are also addressed in these guidelines. The formation of these guidelines is an important first step towards improving the education of veterinarians specifically regarding best-practice for the diagnosis, treatment and control of canine and feline parasites in the tropics.
Asunto(s)
Enfermedades de los Gatos , Enfermedades de los Perros , Enfermedades Parasitarias en Animales , Zoonosis , Animales , Enfermedades de los Gatos/diagnóstico , Enfermedades de los Gatos/tratamiento farmacológico , Enfermedades de los Gatos/prevención & control , Gatos , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/tratamiento farmacológico , Enfermedades de los Perros/prevención & control , Perros , Enfermedades Parasitarias en Animales/diagnóstico , Enfermedades Parasitarias en Animales/tratamiento farmacológico , Enfermedades Parasitarias en Animales/prevención & control , Clima Tropical , Zoonosis/diagnóstico , Zoonosis/tratamiento farmacológico , Zoonosis/prevención & controlRESUMEN
BACKGROUND: Wild carnivores living alongside humans and domestic animals are vulnerable to changes in the infectious disease dynamics in their populations. The aims of this study were to determine the prevalence and diversity of selected tick-borne pathogens (TBPs) of veterinary and/or zoonotic concern in wild populations of caracals (Caracal caracal) occurring in human-modified landscapes in South Africa. Using molecular techniques, we screened 57 caracal blood samples for infection by rickettsial bacteria and piroplasms in three regions of South Africa: rangeland in the Central Karoo (n = 27) and Namaqualand (n = 14) as well as the urban edge of the Cape Peninsula (n = 16) of South Africa. To characterise pathogen identity, we sequenced the 18S rRNA and 16S rRNA genes from positive samples and analysed sequences within a phylogenetic framework. We also examine the diversity of potential tick vectors. RESULTS: All individuals tested were infected with at least one tick-borne pathogen. Pathogens included Hepatozoon felis, Babesia felis, Babesia leo and a potentially novel Babesia species. An Anaplasma species previously described in South African domestic dogs was also found in 88% of urban edge caracals. Higher rates of co-infection characterised urban edge caracals (81% vs 15% and 0% in the two rangeland populations), as well as a greater incidence of mixed infections. Host attached tick species include Haemaphysalis elliptica, an important pathogen vector among carnivore hosts. CONCLUSIONS: This study confirms the occurrence of previously undocumented tick-borne pathogens infecting free-ranging caracals in human-modified landscapes. We identify clear differences in the pathogen profiles among our study populations and discuss the likely health costs to caracals living adjacent to urban areas.
Asunto(s)
Felidae/microbiología , Insectos Vectores/microbiología , Insectos Vectores/parasitología , Enfermedades por Picaduras de Garrapatas/epidemiología , Enfermedades por Picaduras de Garrapatas/microbiología , Enfermedades por Picaduras de Garrapatas/parasitología , Garrapatas/microbiología , Garrapatas/parasitología , Anaplasma/clasificación , Anaplasma/genética , Anaplasma/aislamiento & purificación , Animales , Animales Domésticos , Animales Salvajes/microbiología , Babesia/clasificación , Babesia/genética , Babesia/aislamiento & purificación , Gatos , Coccidios/clasificación , Coccidios/genética , Coccidios/aislamiento & purificación , Coinfección/microbiología , Coinfección/parasitología , Perros , Humanos , Filogenia , ARN Ribosómico 16S/genética , ARN Ribosómico 18S/genética , Rickettsia/clasificación , Rickettsia/genética , Rickettsia/aislamiento & purificación , Sudáfrica/epidemiología , Enfermedades por Picaduras de Garrapatas/diagnósticoRESUMEN
This is the first comprehensive review of the literature pertaining to Babesia species reported from domestic cats. Description of the four species (Babesia felis, Babesia cati, Babesia herpailuri, and Babesia pantherae) named based on morphology and/or host specificity is documented. Feline babesiosis is of major veterinary concern only in South Africa. Reports of the rare occurrence of feline babesiosis cases in Europe (France, Germany, Poland, and Spain) and Asia (Israel, India, and Pakistan) are documented. Molecular characterization has revealed that cats can harbor a variety of Babesia species. The previous practice of referring to all piroplasms, especially small ones, seen on feline blood smears as B. felis is therefore no longer tenable. The near-full-length 18S rRNA gene sequences entered into GenBank in 2001 (accession no. AF244912) are designated as definitive for B. felis sensu stricto. All published literature relating to molecular characterization of feline Babesia species that could be traced was critically assessed. Four Babesia species are now known to be involved in causing feline babesiosis in South Africa: the closely related B. felis s.s. and Babesia leo (clade I), Babesia lengau (clade II), and Babesia species cat Western Cape (clade VI, Babesia s.s.). Clade VI also includes Babesia canis presentii and Babesia hongkongensis reported from cats in Asia. Six other Babesia species have been reported from domestic cats: the dog-associated B. canis s.s., Babesia gibsoni, and B. vogeli, as well as Babesia lohae, Babesia microti, and Babesia vulpes. Phylogenetic relationships of all named species were assessed and are presented as trees. The relatively high prevalence of B. vogeli in clinically healthy cats (16% in Brazil, 13% on St Kitts, and 8.1% in Portugal) suggests that immunocompetent cats can harbor the infection with no discernible untoward effects. Reports of occurrence of B. felis and other Babesia species in domestic cats should be accepted only if they are supported by credible molecular provenance.
RESUMEN
For most of the 20th century the causative agent of canine babesiosis, wherever it occurred in the world, was commonly referred to as Babesia canis. Early research, from the 1890s to the 1930s, had shown that there were three distinctly different vector-specific parasite entities occurring in specific geographical regions, that host response to infection ranged from subclinical to acute, and that immunity to one stock of the parasite did not necessarily protect against infection with other stocks. This substantial body of knowledge was overlooked or ignored for 50 years. In this review the first records and descriptions of the disease in four geographical regions were traced: sub-Saharan Africa, Europe, North Africa and Asia. Research leading to identification of the specific tick vector species involved is documented. Evidence is given of the growing realisation that there were substantial biological differences between stocks originating from different geographical regions. Etymological provenance for Babesia vogeli is proposed.
Asunto(s)
Babesia/clasificación , Babesiosis/parasitología , Enfermedades de los Perros/parasitología , África del Sur del Sahara/epidemiología , África del Norte/epidemiología , Animales , Asia/epidemiología , Babesia/inmunología , Babesia/patogenicidad , Vectores de Enfermedades , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/inmunología , Perros , Europa (Continente)/epidemiologíaRESUMEN
In sub-Saharan Africa, virulent babesiosis in domestic dogs is primarily caused by Babesia rossi. Black-backed jackals (Canis mesomelas), indigenous hosts of B. rossi, are the most likely reservoir from which B. rossi became established in domestic dog populations in South Africa. Haemaphysalis elliptica is the only confirmed vector transmitting B. rossi to domestic dogs; very little was known about the prevalence of H. elliptica infestation in black-backed jackal populations. All jackals (nâ¯=â¯9) from a site in Gauteng Province, South Africa, were infested with H. elliptica, which was also the most numerous tick recovered. Rhipicephalus simus was the second-most prevalent tick. Low numbers of four other tick species were recovered. An extended dataset (nâ¯=â¯23) including published data on adult black-backed jackals (nâ¯=â¯14) from other parts of South Africa indicated that H. elliptica (74%) was the most prevalent species, followed by R. simus (44%). Published data from black-backed jackals (nâ¯=â¯12) in Kenya showed a prevalence of H. leachi sensu lato infestation of 93%. We conclude that where its off-host ecological requirements are met, H. elliptica/leachi is the most prevalent tick infesting black-backed jackal population throughout their range. A comprehensive checklist, with discussion, is given for the 29 tick species reported from black-backed jackals in both southern and northeastern Africa.
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Babesia/aislamiento & purificación , Reservorios de Enfermedades/veterinaria , Ixodidae/microbiología , Chacales , Infestaciones por Garrapatas/veterinaria , Animales , Reservorios de Enfermedades/microbiología , Vectores de Enfermedades , Prevalencia , Sudáfrica/epidemiología , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/parasitologíaRESUMEN
Dogs are the main reservoir of Leishmania infantum and in some countries have been regularly culled as part of government policy to control visceral leishmaniasis. At the 13th Symposium of the Companion Vector-Borne Diseases World Forum in Windsor, UK, March 19-22, 2018, we consolidated a consensus statement regarding the usefulness of dog culling as a means of controlling visceral leishmaniasis. The statement highlighted the futility of culling infected dogs, whether healthy or sick, as a measure to control the domestic reservoir of L. infantum and reduce the risk for visceral leishmaniasis.
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Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/prevención & control , Leishmaniasis/veterinaria , Animales , Reservorios de Enfermedades/veterinaria , Enfermedades de los Perros/parasitología , Enfermedades de los Perros/transmisión , Perros , Leishmaniasis Visceral/veterinariaRESUMEN
BACKGROUND: Feline babesiosis, sporadically reported from various countries, is of major clinical significance in South Africa, particularly in certain coastal areas. Babesia felis, B. leo, B. lengau and B. microti have been reported from domestic cats in South Africa. Blood specimens from domestic cats (n = 18) showing clinical signs consistent with feline babesiosis and confirmed to harbour Babesia spp. piroplasms by microscopy of blood smears and/or reverse line blot (RLB) hybridization were further investigated. Twelve of the RLB-positive specimens had reacted with the Babesia genus-specific probe only, which would suggest the presence of a novel or previously undescribed Babesia species. The aim of this study was to characterise these organisms using 18S rRNA gene sequence analysis. RESULTS: The parasite 18S rRNA gene was cloned and sequenced from genomic DNA from blood samples. Assembled sequences were used to construct similarity matrices and phylogenetic relationships with known Babesia spp. Fifty-five 18S rRNA gene sequences were obtained. Sequences from 6 cats were most closely related to published B. felis sequences (99-100% sequence identity), while sequences from 5 cats were most closely related to B. leo sequences (99-100% sequence identity). One of these was the first record of B. leo in Mozambique. One sequence had 100% sequence identity with the published B. microti Otsu strain. The most significant finding was that sequences from 7 cats constituted a novel Babesia group with 96% identity to Babesia spp. previously recorded from a maned wolf (Chrysocyon brachyurus), a raccoon (Procyon lotor) from the USA and feral raccoons from Japan, as well as from ticks collected from dogs in Japan. CONCLUSIONS: Babesia leo was unambiguously linked to babesiosis in cats. Our results indicate the presence of a novel potentially pathogenic Babesia sp. in felids in South Africa, which is not closely related to B. felis, B. lengau and B. leo, the species known to be pathogenic to cats in South Africa. Due to the lack of an appropriate type-specimen, we refrain from describing a new species but refer to the novel organism as Babesia sp. cat Western Cape.
Asunto(s)
Babesia/clasificación , Babesiosis/parasitología , Enfermedades de los Gatos/parasitología , Animales , Babesia/aislamiento & purificación , Babesiosis/sangre , Enfermedades de los Gatos/sangre , Gatos , Tipificación Molecular/veterinaria , Filogenia , ARN Protozoario , ARN Ribosómico 18S , SudáfricaRESUMEN
BACKGROUND: Domestic dogs are not native to sub-Saharan Africa, which may account for their susceptibility to Babesia rossi, of which endemic black-backed jackals (Canis mesomelas) are natural reservoirs. There is virtually no information on the occurrence of potentially pathogenic haemogregarines (e.g. Hepatozoon canis) or even rickettsial bacteria (e.g. Ehrlichia spp. and Anaplasma spp.) in indigenous canids in sub-Saharan Africa. Such organisms could pose a risk to domestic dogs, as well as to populations of endangered indigenous canid species. RESULTS: Genomic DNA extracted from blood samples taken from 126 free-ranging and 16 captive black-backed jackals was subjected to reverse line blot (RLB) hybridization assay; 82 (57.8%) specimens reacted only with the Ehrlichia/Anaplasma genera-specific probe. Full-length bacterial 16S rRNA gene of five of these specimens was cloned and the recombinants sequenced. The ten 16S rDNA sequences obtained were most closely related, with approximately 99% identity, to Anaplasma sp. South African Dog, various uncultured Anaplasma spp., as well as various Anaplasma phagocytophilum genotypes. Ninety-one specimens were screened for haemogregarines through PCR amplification using the 18S rRNA gene; 20 (21.9%) specimens reacted positively, of which 14 (15.4%) were confirmed positive for Hepatozoon genotypes from within H. canis. Two (2.2%) specimens were found positive for two different Hepatozoon genotypes. CONCLUSIONS: Sequence analyses confirmed the presence of 16S rDNA sequences closely related to A. phagocytophilum and Anaplasma sp. South African Dog as well as two H. canis genotypes in both free-ranging and captive black-backed jackals. Distinguishing between closely related lineages may provide insight into differences in pathogenicity and virulence of various Anaplasma and H. canis genotypes. By building up a more comprehensive understanding of the range and diversity of the bacteria and eukaryotic organisms (piroplasms and haemogregarines) in the blood of indigenous canids, we may gain insight to such infections in these often-endangered species and the potential for horizontal transmission to and from domestic dogs via ticks where favourable conditions exist.
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Anaplasma/aislamiento & purificación , Anaplasmosis/epidemiología , Coccidiosis/epidemiología , Eucoccidiida/aislamiento & purificación , Chacales , Anaplasma/genética , Anaplasmosis/sangre , Anaplasmosis/microbiología , Anaplasmosis/parasitología , Animales , Coccidiosis/sangre , Coccidiosis/microbiología , Coccidiosis/parasitología , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/microbiología , Enfermedades de los Perros/parasitología , Perros , Eucoccidiida/genética , Chacales/microbiología , Chacales/parasitología , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Sudáfrica/epidemiologíaRESUMEN
Finding a healthy balance between classical parasitology and clinical veterinary medicine remains a challenge. Veterinary parasitology, of vital interest in sub-Saharan Africa, has always featured prominently at the Faculty of Veterinary Science, University of Pretoria (founded in 1920). The faculty was initially an integral part of the Onderstepoort Veterinary Institute (OVI), and parasitology was taught by specialist researchers from OVI - a cult of total coverage prevailed. Presenting three separate courses - ectoparasitology, helminthology and protozoology - continued for many decades. From 1949 to 1973 an attendance course in veterinary parasitology was presented in the final academic year. This was revived in 1995, with a "refresher" in parasitology for final-year students (during their clinic rotation), including diagnostic parasite identification and problem-solving group discussions (prepared and led by students). Student contact time (including practical classes and assessments), initially 80â¯h/discipline/year, was gradually reduced. A species-based approach (introduced in 1998) had a major impact - an introductory course in general parasitology was followed by fragmented lectures in the subsequent 2 years on key parasitic diseases in the species-based subjects. In 2013 the curriculum reverted to being discipline-based, i.e. all aspects of parasitology and parasitic diseases covered during one academic year. The 3 sub-disciplines are included in a 2-semester course, with a total contact time of 100â¯h, which barely meets the minimum recommended by the WAAVP. Various lessons learnt are discussed.
Asunto(s)
Educación en Veterinaria , Empleos en Salud/educación , Parasitología/educación , Enseñanza/historia , Academias e Institutos , Animales , Curriculum , Pruebas Diagnósticas de Rutina , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Enfermedades Parasitarias en Animales/diagnóstico , Enfermedades Parasitarias en Animales/epidemiología , Enfermedades Parasitarias en Animales/parasitología , Facultades de Medicina Veterinaria , Sudáfrica/epidemiología , Estudiantes del Área de la Salud , Medicina VeterinariaRESUMEN
BACKGROUND: Babesia rossi, which is transmitted by Haemaphysalis spp. and is highly virulent to domestic dogs, occurs only in sub-Saharan Africa. Since dogs are not native to the region, it has been postulated that the natural host of B. rossi is an indigenous African canid. Although various attempts at artificial infection indicated that black-backed jackals (Canis mesomelas) could become subclinically infected with B. rossi, data on occurrence of B. rossi in free-ranging jackals was lacking. A long-term behaviour study in which free-ranging black-backed jackals were radio-collared offered the opportunity of collecting blood specimens from a large number of free-ranging jackals. METHODS: Genomic DNA was extracted from the EDTA blood samples (n = 107). PCR products were subjected to Reverse Line Blot hybridization using Theileria and Babesia genera-specific as well as 28 species-specific oligonucleotide probes, including Babesia canis, Babesia rossi, Babesia vogeli and Babesia gibsoni. The near full-length parasite 18S rRNA gene was amplified from two selected samples (free-ranging jackals), cloned and a total of six recombinants were sequenced. RESULTS: Of 91 free-ranging jackals, 77 (84.6%) reacted with the Babesia genus-specific probe; 27 (29.7%) also reacted with the B. rossi probe. Of 16 captive jackals, 6 (37.5%) reacted with the B. rossi probe, while one further sample reacted with the Babesia genus-specific probe only. After cloning, 6 recombinants yielded identical sequences identical to that of B. rossi (L19079) and differing by 2 base pairs from B. rossi (DQ111760) in GenBank. The observed sequence similarities were confirmed by phylogenetic analyses using neighbour joining and maximum parsimony. CONCLUSIONS: Black-backed jackals are natural hosts of B. rossi.
Asunto(s)
Babesia/aislamiento & purificación , Babesiosis/epidemiología , Babesiosis/parasitología , Reservorios de Enfermedades , Enfermedades de los Perros/epidemiología , Chacales/parasitología , África del Sur del Sahara/epidemiología , Animales , Babesia/genética , Babesia/patogenicidad , Babesiosis/sangre , Enfermedades de los Perros/sangre , Enfermedades de los Perros/parasitología , Perros , Hibridación de Ácido Nucleico , Filogenia , Reacción en Cadena de la Polimerasa/veterinariaRESUMEN
The objective of our study was identification and molecular characterization of piroplasms and rickettsias occurring in brown (Parahyaena brunnea) and spotted hyaenas (Crocuta crocuta) from various localities in Namibia and South Africa. Whole blood (n = 59) and skin (n = 3) specimens from brown (n = 15) and spotted hyaenas (n = 47) were screened for the presence of Babesia, Theileria, Ehrlichia and Anaplasma species using the reverse line blot (RLB) hybridization technique. PCR products of 52/62 (83.9%) of the specimens hybridized only with the Theileria/Babesia genus-specific probes and not with any of the species-specific probes, suggesting the presence of a novel species or variant of a species. No Ehrlichia and/or Anaplasma species DNA could be detected. A parasite 18S ribosomal RNA gene of brown (n = 3) and spotted hyaena (n = 6) specimens was subsequently amplified and cloned, and the recombinants were sequenced. Homologous sequence searches of databases indicated that the obtained sequences were most closely related to Babesia lengau, originally described from cheetahs (Acinonyx jubatus). Observed sequence similarities were subsequently confirmed by phylogenetic analyses which showed that the obtained hyaena sequences formed a monophyletic group with B. lengau, B abesia conradae and sequences previously isolated from humans and wildlife in the western USA. Within the B. lengau clade, the obtained sequences and the published B. lengau sequences were grouped into six distinct groups, of which groups I to V represented novel B. lengau genotypes and/or gene variants. We suggest that these genotypes cannot be classified as new Babesia species, but rather as variants of B. lengau. This is the first report of occurrence of piroplasms in brown hyaenas.
Asunto(s)
Anaplasma/clasificación , Babesia/clasificación , Ehrlichia/clasificación , Hyaenidae/parasitología , Theileria/clasificación , Anaplasma/genética , Anaplasma/aislamiento & purificación , Animales , Animales Salvajes/microbiología , Animales Salvajes/parasitología , Babesia/genética , Babesia/aislamiento & purificación , Babesiosis/epidemiología , ADN Bacteriano/genética , ADN Protozoario/genética , Ehrlichia/genética , Ehrlichia/aislamiento & purificación , Genotipo , Namibia , Técnicas de Amplificación de Ácido Nucleico , Hibridación de Ácido Nucleico , Filogenia , Reacción en Cadena de la Polimerasa , ARN Ribosómico 18S/genética , Homología de Secuencia , Sudáfrica , Theileria/genética , Theileria/aislamiento & purificaciónRESUMEN
Although there is evidence of high seroprevalence of antibodies to Babesia spp. in dogs in central Namibia, clinical babesiosis is rarely diagnosed. Rhipicephalus sanguineus sensu lato, the vector of Babesia vogeli, is common in Namibia while Haemaphysalis elliptica, the vector of the highly virulent but morphologically indistinguishable Babesia rossi, has rarely been recorded, mainly in northern Namibia. On the basis of vector occurrence, clinical cases of canine babesiosis in Windhoek, central Namibia, have been ascribed to B. vogeli. DNA extracted from a blood smear made from a sick dog was subjected to the reverse line blot hybridisation assay. The polymerase chain reaction amplicons hybridised with the B. vogeli-specific probe, but not with the Babesia canis- and B. rossi-specific probes. Although attempts at cloning and sequencing of the full-length 18S rRNA gene were unsuccessful, we can confirm that B. vogeli occurs in central Namibia.
Asunto(s)
Babesia/aislamiento & purificación , Babesiosis/parasitología , Enfermedades de los Perros/parasitología , Animales , Babesia/clasificación , Perros , Masculino , NamibiaRESUMEN
Ticks were collected from 191 cheetahs at three breeding centres in North West and Limpopo Provinces, South Africa. Haemaphysalis elliptica, a common tick of large felids, was the most abundant species collected, while Amblyomma hebraeum and Rhipicephalus simus occurred in lower numbers. In addition to these three species, drag-sampling of the vegetation revealed the presence of Amblyomma marmoreum, Rhipicephalus (B.) decoloratus and Rhipicephalus zambeziensis. The presence of free-ranging antelopes, murid rodents and tortoises at the breeding centres probably contributed to the availability of immature tick stages on the vegetation. Diurnal and seasonal questing patterns of ixodid ticks were investigated at monthly intervals at the largest cheetah-breeding centre. Questing ticks were most abundant on the vegetation during the warm summer months. Most questing H. elliptica larvae and nymphs were collected from the vegetation in the early morning and late afternoon and fewest during the middle of the day.
Asunto(s)
Acinonyx/parasitología , Biodiversidad , Ixodidae/fisiología , Infestaciones por Garrapatas/veterinaria , Animales , Antílopes/parasitología , Cruzamiento , Ixodidae/clasificación , Larva/fisiología , Estadios del Ciclo de Vida , Roedores/parasitología , Estaciones del Año , Sudáfrica/epidemiología , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/parasitología , Tortugas/parasitologíaRESUMEN
BACKGROUND: Canine babesiosis caused by Babesia rossi, transmitted by Haemaphysalis elliptica in South Africa, has also been reported from Nigeria. Although H. leachi (sensu lato) is widespread in sub-Saharan Africa, published literature on the occurrence of canine babesiosis is meagre. It has been postulated that the genotype of Babesia rossi Erythrocyte Membrane Antigen 1 (BrEMA1) may be linked to virulence of the specific isolate. The primary objective of this study was to detect and characterise tick-borne pathogens in dogs presented to a veterinary hospital using molecular techniques. In B. rossi-positive specimens, we aimed to determine whether the BrEMA1 gene occurred and to compare genotypes with those found in other isolates. Lastly, we wished to identify the tick species that were recovered from the sampled dogs. METHODS: Blood specimens (n = 100) were collected during January to March 2010 from domestic dogs presented at an animal hospital in Jos, Plateau State, Nigeria. They were screened for the presence of Babesia/Theileria and Ehrlichia/Anaplasma genomic DNA using PCR and Reverse Line Blot (RLB) assays. Positive B. rossi specimens were tested for the presence of the BrEMA1gene using an RT-PCR. In addition, ticks were collected from dogs found to be infested during sampling. RESULTS: On RLB, 72 (72%) of the specimens were positive for one or more haemoparasites. Of the positive specimens, 38 (53%) were infected with B. rossi; 9 (13%) with Theileria sp. (sable); 5 (7%) with either Ehrlichia canis or Anaplasma sp. Omatjenne, respectively; 3 (4%) with Theileria equi; and 1 (1%) with B. vogeli and E. ruminantium, respectively. Co-infections were detected in 13 (18%) of the specimens. Results of RT-PCR screening for the BrEMA1 gene were negative. A total of 146 ticks belonging to 8 species were collected and identified: Rhipicephalus sanguineus 107 (73%), Haemaphysalis leachi (sensu stricto) 27 (18%), R. turanicus 3 (2%), and Amblyomma variegatum, H. elliptica, R. lunulatus, R. muhsamae and R. senegalensis 1 (1%), respectively. CONCLUSIONS: Up to 8 tick-borne pathogens possibly occur in the dog population at Jos, with B. rossi being the most prevalent. The absence of the BrEMA1 gene suggests that B. rossi occurring in that area may be less virulent than South African isolates.