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1.
Rev Bras Parasitol Vet ; 30(1): e023020, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33605388

RESUMO

Neospora caninum is considered to be one of the main causes of abortion among cattle. The present survey was conducted in the municipality of Rolim de Moura, Rondônia State, Brazil. A questionnaire that investigates the epidemiological aspects of neosporosis was used in the analysis of risk factors associated with the animal-level and herd-level prevalence in dairy cattle. A total of 416 bovine blood samples were collected from 30 farms, and N. caninum antibody levels were measured by Indirect Fluorescent Antibody Test (IFAT). Analysis of dairy cattle serum samples revealed the presence of anti-N. caninum antibodies to be 47.36% (n = 197). Risk factors associated with N. caninum infection were the management system and access locations of dogs. The results of the present survey indicated that infection of dairy cattle with N. caninum is widespread in the studied region of Western Amazon, which has implications for prevention and control of neosporosis in this region. Therefore, integrated control strategies and measures are recommended to prevent and control N. caninum infection in dairy cattle. In addition, direct contact between dairy cattle, dogs and wild animals, which can influence the epidemiology of neosporosis, should be investigated further.


Assuntos
Doenças dos Bovinos , Coccidiose , Neospora , Animais , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/transmissão , Coccidiose/epidemiologia , Coccidiose/prevenção & controle , Coccidiose/transmissão , Coccidiose/veterinária , Indústria de Laticínios , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Cães , Análise Fatorial , Feminino , Neospora/imunologia , Gravidez , Fatores de Risco , Estudos Soroepidemiológicos
2.
Parasitol Res ; 119(9): 3023-3031, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32725320

RESUMO

Hepatozoon canis is a hemoprotozoan organism that infects domestic and wild carnivores throughout much of Europe. The parasite is mainly transmitted through the ingestion of infected ticks containing mature oocysts. The aims of the present survey were to determine the prevalence of H. canis in hunting dogs living in Southern Italy and to assess potential infection risk factors. DNA extracted from whole blood samples, collected from 1433 apparently healthy dogs living in the Napoli, Avellino, and Salerno provinces of Campania region (Southern Italy), was tested by a quantitative real-time polymerase chain reaction (qPCR) assay to amplify H. canis. Furthermore, the investigated dog population was also screened by qPCR for the presence of Ehrlichia canis, a major tick-borne pathogen in Southern Italy, in order to assess possible co-infections. Two hundred dogs were H. canis PCR-positive, resulting in an overall prevalence of 14.0% (CI 12.2-15.9). Breed category (P < 0.0001), hair coat length (P = 0.015), and province of residence (P < 0.0001) represented significant risk factors for H. canis infection. The presence of H. canis DNA was also significantly associated with E. canis PCR positivity (P < 0.0001). Hunting dogs in Campania region (Southern Italy) are frequently exposed to H. canis, and the infection is potentially associated with close contact with wildlife. Further studies are needed to assess the pathogenic potential of H. canis, as well as the epidemiological relationships between hunting dogs and wild animal populations sharing the same habitats in Southern Italy.


Assuntos
Coccidiose/veterinária , Doenças do Cão/parasitologia , Eucoccidiida/isolamento & purificação , Animais , Coccidiose/parasitologia , Coccidiose/transmissão , Doenças do Cão/sangue , Doenças do Cão/epidemiologia , Doenças do Cão/transmissão , Cães , Eucoccidiida/genética , Eucoccidiida/fisiologia , Feminino , Itália/epidemiologia , Masculino , Reação em Cadeia da Polimerase , Fatores de Risco , Carrapatos/parasitologia , Carrapatos/fisiologia
3.
Parasitol Res ; 118(7): 2311-2315, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31093752

RESUMO

The role of the American cockroach, Periplaneta americana as transport host for Eimeria tenella was evaluated. Twenty-four cockroaches were orally fed with sporulated oocysts of E. tenella. Their feces and digestive tract were examined for oocysts by sugar centrifugal flotation technique and PCR. Infectivity of the oocysts recovered from the digestive tract of infected cockroaches as well as from their feces was evaluated by orally inoculating them into Boris Brown chickens. E. tenella oocysts were found in the digestive tract and feces of infected cockroaches up to day 4 after ingestion of oocysts. Furthermore, oocysts that were recovered from the digestive tract and feces of cockroaches remained infective for 4 and 3 days after ingestion of oocysts, respectively. Presence of oocysts in the feces of chicken that had been inoculated with either digestive tract or feces of P. americana demonstrated the infectivity of E. tenella oocysts from digestive tract or feces, suggesting that P. americana may play a role in the transmission of E. tenella among chicken and between chicken flocks.


Assuntos
Galinhas/parasitologia , Coccidiose/veterinária , Eimeria tenella/isolamento & purificação , Periplaneta/parasitologia , Doenças das Aves Domésticas/transmissão , Animais , Coccidiose/parasitologia , Coccidiose/transmissão , Eimeria tenella/genética , Fezes/parasitologia , Oocistos , Doenças das Aves Domésticas/parasitologia
4.
Parasitol Res ; 118(6): 1875-1883, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30945017

RESUMO

Neosporosis in cattle is a globally important disease, causing abortions and significant economic losses if epidemic abortions occur. In Serbia, however, studies of Neospora caninum infection in cattle are few and are based on limited samples and/or from limited areas. We thus performed a nationwide study to examine the seroprevalence of N. caninum infection in a sample of cows randomly selected from dairy farms in 12 epidemiological units from throughout Serbia, as well as the possible transmission risk factors. Sera from a total of 1496 cattle were tested by competitive ELISA, and N. caninum-specific antibodies were shown in 7.2% animals (95% confidence interval CI, 6.6-7.9%), ranging from 2.2 to 12% across the epidemiological units. At least one seropositive animal was detected on 10.7% (95% CI, 9.7-11.8%) of farms, with a range of 5.9-25.9%. Logistic regression analysis showed that the single risk factor for infection in individual animals was keeping cows in loose-stalls (OR = 3.31, 95% CI = 1.95-5.60, P < 0.001). Risk factors for the presence of infection on farms also included housing in loose-stalls (OR = 18.49, 95% CI = 5.40-63.36, P < 0.001), and herd size > 100 animals (OR = 24.08, 95% CI = 3.85-150.50, P = 0.001). In view of the relatively low prevalence of infection showed at both the individual and farm level, this is the perfect time to undertake appropriate preventive measures to improve animal health and reduce economic losses.


Assuntos
Anticorpos Antiprotozoários/sangue , Doenças dos Bovinos/epidemiologia , Coccidiose/epidemiologia , Coccidiose/veterinária , Neospora/imunologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/transmissão , Coccidiose/transmissão , Ensaio de Imunoadsorção Enzimática/veterinária , Fazendas , Feminino , Neospora/isolamento & purificação , Gravidez , Prevalência , Fatores de Risco , Sérvia , Estudos Soroepidemiológicos
5.
Poult Sci ; 98(8): 3176-3180, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30953077

RESUMO

The purpose of this study was to determine if Eimeria oocysts recovered from litter at the time of chick placement in commercial broiler houses contained oocysts that were infectious for chickens. Over 100 litter samples were collected from 30 poultry farms representing a total of 60 different broiler houses with 9 houses sampled more than once over 1.5 yr. The samples were collected just before the placement of newly hatched chicks and after an anticoccidial drug (ACD) or Eimeria vaccine (VAC) program, and processed for counting oocysts followed by Eimeria species determination using ITS1 PCR. Broiler chicks were inoculated with recovered Eimeria oocysts to determine if the litter oocysts were viable and capable of causing patent infection. At placement, E. maxima (Emax) oocysts were detected in 70 of 75 houses after ACD program and 46 of 47 houses after VAC program. Eimeria acervulina, E. praecox, and/or E. tenella (Eapt) were detected in 75 of 75 houses after ACD program and 47 of 47 houses after VAC program. Viability testing revealed that 33.0% of broiler houses contained viable Emax oocysts, while 46.9% contained viable Eapt oocysts. During VAC programs, the concentration of Emax oocysts at placement and the total number of Emax oocysts shed by chickens in viability studies showed a very strong correlation (r = 0.83). Likewise, during ACD programs, the concentration of Eapt oocysts at placement and the total number of Eapt oocysts shed by chickens in the viability study showed a strong correlation (r = 0.62). In general, Eimeria oocyst levels at placement and number of viable oocysts shed by chickens in the viability study were similar among houses on the same farm. However, the number of Eimeria oocysts shed in the viability studies was considerably less than expected based on the number of oocysts given. These data suggest that nearly 100% of all poultry houses contain Emax and Eapt oocysts at placement with 30 to 50% of the houses containing viable Eimeria oocysts, thus possibly representing a source of the protozoa to newly hatched chicks.


Assuntos
Coccidiose/veterinária , Eimeria/isolamento & purificação , Oocistos/isolamento & purificação , Doenças das Aves Domésticas/transmissão , Animais , Animais Recém-Nascidos , Galinhas , Coccidiose/prevenção & controle , Coccidiose/transmissão , Coccidiostáticos/administração & dosagem , Abrigo para Animais , Doenças das Aves Domésticas/parasitologia , Doenças das Aves Domésticas/prevenção & controle , Vacinas Protozoárias/administração & dosagem , Vacinação/veterinária
6.
Vet Immunol Immunopathol ; 208: 53-57, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30712792

RESUMO

Neospora caninum infection of cattle can be vertically transmitted, resulting in abortion or birth of infected calves. Vertical transmission occurs both in acutely or chronically infected cattle. There is little information on the immune response needed to prevent endogenous transplacental transmission, particularly from chronically infected cattle to their offspring in a natural environment. In this study, N. caninum seropositive pregnant cattle from three different farms with high avidity antibodies and low IgM titers were selected and their newborn colostrum-deprived calves were tested for anti-N. caninum antibodies. Based on these results, dams were grouped according to their congenital transmission status. The analysis of the immune profile of the chronically-infected pregnant cattle revealed that higher ratio between IgG1 and IgG2 anti-N. caninum serum titers and higher levels of systemic IFN-γ were associated with diminished vertical transmission rates, compared to dams with the opposite profile. Our results evidenced an association between the immune profile and vertical transmission in non-aborting chronically infected dams, and confirm that vertical transmission, even when not leading to abortion, is related to a defined immune profile. This is important information to accomplish successful vaccine development efforts.


Assuntos
Coccidiose/imunologia , Coccidiose/transmissão , Imunoglobulina G/sangue , Transmissão Vertical de Doença Infecciosa/veterinária , Interferon gama/sangue , Aborto Animal/imunologia , Animais , Animais Recém-Nascidos , Anticorpos Antiprotozoários/sangue , Bovinos , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/transmissão , Indústria de Laticínios , Ensaio de Imunoadsorção Enzimática , Feminino , Imunoglobulina M/sangue , Masculino , Neospora , Gravidez , Complicações Parasitárias na Gravidez/veterinária
7.
Trop Anim Health Prod ; 51(6): 1751-1755, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30706331

RESUMO

Neospora caninum is considered as one of the main causes of reproductive failure in cattle. Vertical transmission is the main route of infection in the bovine host and plays an important role in maintaining the parasite in the herd. Molecular detection of N. caninum is important to determine the occurrence of the disease and to evaluate the genetic diversity of the parasite. The present study aimed at assessing the vertical transmission of N. caninum using molecular techniques to detect the parasite in tissue samples from bovine fetuses collected in a slaughterhouse in the state of São Paulo, Brazil. Seventy fetuses and 70 blood samples from pregnant cows were collected in a slaughtering line. Fresh samples of heart and brain tissue from fetuses were analyzed using molecular assays. Serum samples from fetuses and cows were subjected to an indirect fluorescent antibody test (IFAT) to detect antibodies against N. caninum. Nested PCR targeting the internal transcriber 1 (ITS1) region of the protozoan organism was used in the molecular testing. From the total of fetuses examined, 71.42% were positive for N. caninum by PCR. A higher number of heart samples (47.1%) were positive for the parasite using this technique. Antibodies against the protozoa were detected in 12.9% of serum samples of cows; 2.8% of fetuses were seropositive for this pathogen. Our results show that vertical transmission of N. caninum occurs in cattle from this region of Brazil, and that the use of different diagnostic techniques contributes to successful diagnosis of congenital transmission of the parasite in cattle.


Assuntos
Doenças dos Bovinos/parasitologia , Coccidiose/veterinária , Feto/parasitologia , Transmissão Vertical de Doença Infecciosa/veterinária , Neospora/isolamento & purificação , Matadouros , Animais , Anticorpos Antiprotozoários/sangue , Bioensaio , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/transmissão , Coccidiose/epidemiologia , Coccidiose/transmissão , Feminino , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Neospora/imunologia , Reação em Cadeia da Polimerase , Gravidez
8.
Med Vet Entomol ; 33(2): 247-255, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30666684

RESUMO

Cattle besnoitiosis caused by Besnoitia besnoiti (Eucoccidiorida: Sarcocystidae) is a re-emerging disease in Europe. Its mechanical transmission by biting flies has not been investigated since the 1960s. The aim of this study was to re-examine the ability of Stomoxys calcitrans (Diptera: Muscidae) to transmit virulent B. besnoiti bradyzoites from chronically infected cows to susceptible rabbits. Three batches of 300 stable flies were allowed to take an interrupted bloodmeal on chronically infected cows, followed by an immediate bloodmeal on three rabbits (Group B). A control group of rabbits and a group exposed to the bites of non-infected S. calcitrans were included in the study. Blood quantitative polymerase chain reaction (qPCR) analyses, and clinical, serological and haematological surveys were performed in the three groups over 152 days until the rabbits were killed. Quantitative PCR analyses and histological examinations were performed in 24 tissue samples per rabbit. Only one rabbit in Group B exhibited clinical signs of the acute phase of besnoitiosis (hyperthermia, weight loss, regenerative anaemia and transient positive qPCR in blood) and was seroconverted. Parasite DNA was detected in four tissue samples from this rabbit, but no cysts were observed on histological examination. These findings indicate that S. calcitrans may act as a mechanical vector of B. besnoiti more efficiently than was previously considered.


Assuntos
Doenças dos Bovinos/transmissão , Coccidiose/veterinária , Insetos Vetores/fisiologia , Muscidae/fisiologia , Coelhos , Sarcocystidae/fisiologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Coccidiose/parasitologia , Coccidiose/transmissão
9.
Eur J Protistol ; 67: 71-76, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30481662

RESUMO

Intranuclear coccidiosis of testudines (known as TINC) is an emerging disease in chelonians. Although endogenous stages were repeatedly detected in various tissues, attempts to find the oocysts in faeces failed, leaving the question of the transmission and classification of the causative agent of TINC unresolved. We recorded small spherical oocysts (∼6-7 µm in diameter) of an eimeriid coccidium in faeces of a leopard tortoise (Stigmochelys pardalis). Sporulated oocysts were used for the experimental oral inoculation of juvenile coccidia-free tortoises representing 5 species (S. pardalis, Testudo graeca, T. hermanni, T. horsfieldii, and Geochelone sulcata). The oocysts' association with TINC was confirmed based on clinical signs, histopathological findings of intranuclear endogenous stages of the coccidium in many organs (including intestine), and by the partial 18S rDNA sequence analysis of the DNA isolated from organs of the experimentally infected animals and from a single naturally infected as well as from all experimentally infected tortoises. Breeding colonies of chelonians should be screened for this pathogen in order to prevent its further spread and unwanted introduction into endangered free-ranging chelonian populations.


Assuntos
Coccidiose/veterinária , Eimeriidae/classificação , Eimeriidae/fisiologia , Doenças Parasitárias em Animais/parasitologia , Tartarugas/parasitologia , Animais , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Coccidiose/transmissão , Eimeriidae/genética , Eimeriidae/isolamento & purificação , Fezes/parasitologia , Oocistos , Doenças Parasitárias em Animais/prevenção & controle , Doenças Parasitárias em Animais/transmissão , RNA Ribossômico 18S/genética
10.
Artigo em Inglês | MEDLINE | ID: mdl-30017081

RESUMO

Neospora caninum and Toxoplasma gondii are two closely related protozoan parasites that have been detected from various species of bird hosts. However, little is known about the prevalence of N. caninum and T. gondii in crows. Hence, we examined the molecular frequency of N. caninum and T. gondii in the brain samples of hooded crows (Corvus cornix) that collected from different public parks of Tehran, Iran by nested-PCR method. We used the primers targeting the Nc5 and GRA6 genes for detection of N. caninum and T. gondii, respectively. From a total of 55 brain samples, 5 (9.9%) and 9 (16.36%) samples were positive for N. caninum and T. gondii, respectively. Sequencing of a N. caninum isolate revealed 95%-100% identity with the deposited N. caninum in GenBank. Genotyping of T. gondii isolates by PCR-RFLP analysis of the GRA6 gene revealed type III genotype in 8 isolates. The results of this study indicate that hooded crows may have a putative role in transmission of N. caninum and T. gondii to canines and felines definitive hosts, respectively.


Assuntos
Doenças das Aves/epidemiologia , Coccidiose/veterinária , Corvos/parasitologia , Neospora/genética , Toxoplasma/genética , Toxoplasmose Animal/epidemiologia , Animais , Doenças das Aves/parasitologia , Doenças das Aves/transmissão , Encéfalo/parasitologia , Gatos , Coccidiose/epidemiologia , Coccidiose/parasitologia , Coccidiose/transmissão , DNA de Protozoário/genética , Cães , Genótipo , Irã (Geográfico)/epidemiologia , Neospora/classificação , Neospora/isolamento & purificação , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Prevalência , Toxoplasma/classificação , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/parasitologia , Toxoplasmose Animal/transmissão
11.
Vet Parasitol ; 256: 58-70, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29887031

RESUMO

There is considerable confusion concerning validity of Eimeria species in equids, and endogenous developmental stages and pathogenicity of equid Eimeria. This paper summarizes worldwide information on history, structure, life cycle, pathogenicity, prevalence, epidemiology, and diagnosis of Eimeria infections in equids. The following conclusions were drawn. Although three species of Eimeria; E. solipedum, E. uninugulata, and E. leuckarti were named from horses, only E. leuckarti is a valid species infecting equids, including horses, donkeys and zebra. We consider E. solipedum, E. uninugulata and Isospora sp.as spurious/contaminants with coccidia from other hosts. E. leuckarti oocysts are distinctive, dark brown and up to 94 µm long and up to 79 µm wide. Its gametogonic stages and oocysts are present in the lamina propria of small intestines. In equids naturally infected with E. leuckarti, only sexual stages have been confirmed. In most of the approximately 50 cases of histologically diagnosed cases of E. leuckarti infection, this infection was considered coincidental or of no clinical relevance. However, in some cases E. leuckarti was considered pathogenic, causing diarrhea and enteritis. The prepatent period is long, 30-37 days or more in experimentally infected equids. Natural infections have been found in 4 week-old foals, indicating that foals can become infected on the day of birth. The number of oocysts excreted is not correlated with clinical signs.


Assuntos
Coccidiose/veterinária , Equidae , Doenças dos Cavalos/epidemiologia , Animais , Coccidiose/epidemiologia , Coccidiose/transmissão , Eimeria/fisiologia , Doenças dos Cavalos/transmissão , Cavalos
12.
Acta Parasitol ; 63(2): 416-421, 2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-29654669

RESUMO

The aim of this study was to describe the frequency of ovine specific antibodies to Toxoplasma gondii, Neospora caninum and Sarcocystis spp. and to estimate different transmission routes of these infections. One hundred and thirty Texel sheep and their 117 Texel lambs were included in the study. Serum samples were tested for antibodies to T. gondii, N. caninum and Sarcocystis spp. using IFAT. Toxoplasma gondii seroprevalence was 10.00% in sheep (IC95%: 4.80-15.20%), being higher in adult sheep (≥12 year) than in younger sheep (OR 1.30; 95% CI, 1.10-1.50). N. caninum and Sarcocystis spp. seroprevalences were 1.54% (IC95%: 0.00-5.70) and 72.09% (IC95%: 67.70-82.70), respectively, with no association between age and seropositivity in sheep (P>0.05). T. gondii seroprevalence in lambs was 4.27% (IC95%: 0.61-7.94). No association between T. gondii serological status in sheep and their lambs was detected (P = 0.07). Two T. gondii and Sarcocystis spp. seropositive lambs were euthanized and T. gondii and Sarcocystis spp. DNA was detected by PCR in their tissues. In conclusion, the increase of T. gondii seropositivity in relationship with sheep age and the lack of association between sheep-lamb serological status, suggest that horizontal infection is the main transmission route in this flock as reported before. Due to the low number of N. caninum-seropositive ewes no assumptions can be done about the impact of this parasite in this flock. According with previous reports, the main transmission route for Sarcocystis spp. in this species in the present study was horizontal.


Assuntos
Anticorpos Antiprotozoários/sangue , Coccidiose/veterinária , Sarcocistose/veterinária , Doenças dos Ovinos/transmissão , Toxoplasmose Animal/transmissão , Animais , Argentina/epidemiologia , Coccidiose/sangue , Coccidiose/epidemiologia , Coccidiose/transmissão , DNA de Protozoário/genética , Ensaio de Imunoadsorção Enzimática , Técnica Indireta de Fluorescência para Anticorpo , Neospora/genética , Neospora/imunologia , Reação em Cadeia da Polimerase , Sarcocystis/genética , Sarcocystis/imunologia , Sarcocistose/sangue , Sarcocistose/epidemiologia , Sarcocistose/transmissão , Estudos Soroepidemiológicos , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia , Toxoplasma/genética , Toxoplasma/imunologia , Toxoplasmose Animal/sangue , Toxoplasmose Animal/epidemiologia
13.
Ticks Tick Borne Dis ; 9(4): 912-920, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29605549

RESUMO

Species of the genus Hepatozoon (Adeleorina: Hepatozoidae) are arthropod-transmitted protozoan parasites that infect a wide range of vertebrate hosts. In the present study, we describe a new species of Hepatozoon primarily infecting martens and propose the name Hepatozoon martis n. sp., based on its unique morphological, molecular and pathogenic features. The overall prevalence of infection with H. martis n. sp. assessed by PCR in European pine martens (Martes martes) from Bosnia and Herzegovina and stone martens (Martes foina) from Croatia was 100% and 64%, respectively. Gamonts were found in neutrophils and monocytes, and various developmental stages were described in tissue cross-sections. Hepatozoon martis n. sp. shows a high predilection for muscle tissue, and the heart was the most frequently affected organ among the tissues tested by histopathology. Microscopically, pyogranulomatous lesions associated with the presence of the parasitic forms were observed in the cardiac and skeletal muscles of all positive animals examined. Furthermore, the possible existence of alternative, non-vectorial routes of transmission is discussed.


Assuntos
Coccidiose/veterinária , Eucoccidiida/genética , Eucoccidiida/isolamento & purificação , Mustelidae/parasitologia , Infestações por Carrapato/veterinária , Animais , Bósnia e Herzegóvina/epidemiologia , Coccidiose/epidemiologia , Coccidiose/parasitologia , Coccidiose/transmissão , Croácia/epidemiologia , DNA de Protozoário/genética , DNA Ribossômico/genética , Eucoccidiida/patogenicidade , Feminino , Coração/parasitologia , Ixodes/parasitologia , Monócitos/parasitologia , Músculos/parasitologia , Músculos/patologia , Neutrófilos/parasitologia , Filogenia , Reação em Cadeia da Polimerase , Infestações por Carrapato/epidemiologia
14.
Parasitol Int ; 67(4): 397-402, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29614327

RESUMO

Neospora caninum is an obligate intracellular protozoan parasite that infects domestic and wild animals. Canids are considered to be definitive hosts since they may shed oocysts into the environment through their feces. The disease is recognized as one of the major causes of bovine abortion worldwide, leading to important economic losses in the dairy and beef cattle industries. Previous studies have reported N. caninum infection in different species of birds; infection in birds has been associated with increased seroprevalence and reproductive problems in dairy cattle. Although the role of birds in the epidemiological cycle of neosporosis is unknown, birds are exposed to infection because they feed on the ground and could thus contribute to parasite dissemination. This review is focused on the current state of knowledge of neosporosis in birds.


Assuntos
Doenças das Aves/parasitologia , Aves/parasitologia , Coccidiose/parasitologia , Neospora/isolamento & purificação , Aborto Animal/parasitologia , Animais , Anticorpos Antiprotozoários/imunologia , Doenças das Aves/imunologia , Doenças das Aves/transmissão , Bovinos , Doenças dos Bovinos/parasitologia , Coccidiose/imunologia , Coccidiose/transmissão , Fezes/parasitologia , Feminino , Neospora/genética , Neospora/imunologia , Gravidez
15.
Parasitology ; 145(3): 335-344, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28835291

RESUMO

Red fox (Vulpes vulpes) is the most abundant wild canid species in Austria, and it is a well-known carrier of many pathogens of medical and veterinary concern. The main aim of the present study was to investigate the occurrence and diversity of protozoan, bacterial and filarial parasites transmitted by blood-feeding arthropods in a red fox population in western Austria. Blood (n = 351) and spleen (n = 506) samples from foxes were examined by PCR and sequencing and the following pathogens were identified: Babesia canis, Babesia cf. microti (syn. Theileria annae), Hepatozoon canis, Anaplasma phagocytophilum, Candidatus Neoehrlichia sp. and Bartonella rochalimae. Blood was shown to be more suitable for detection of Babesia cf. microti, whilst the spleen tissue was better for detection of H. canis than blood. Moreover, extremely low genetic variability of H. canis and its relatively low prevalence rate observed in this study may suggest that the parasite has only recently been introduced in the sampled area. Furthermore, the data presented here demonstrates, for the first time, the possible vertical transmission of H. canis from an infected vixen to the offspring, and this could explain the very high prevalence in areas considered free of its main tick vector(s).


Assuntos
Artrópodes/parasitologia , Coccidiose/veterinária , Raposas/microbiologia , Raposas/parasitologia , Transmissão Vertical de Doença Infecciosa , Doenças Parasitárias em Animais/epidemiologia , Anaplasma phagocytophilum/genética , Anaplasma phagocytophilum/isolamento & purificação , Anaplasma phagocytophilum/patogenicidade , Animais , Áustria/epidemiologia , Babesia/genética , Babesia/isolamento & purificação , Babesia/patogenicidade , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/parasitologia , Infecções Bacterianas/veterinária , Bartonella/genética , Bartonella/isolamento & purificação , Bartonella/patogenicidade , Coccidiose/epidemiologia , Coccidiose/parasitologia , Coccidiose/transmissão , DNA de Protozoário/genética , Vetores de Doenças , Eucoccidiida/genética , Eucoccidiida/isolamento & purificação , Eucoccidiida/patogenicidade , Doenças Parasitárias em Animais/microbiologia , Doenças Parasitárias em Animais/parasitologia , Reação em Cadeia da Polimerase/veterinária
16.
Vet Parasitol ; 249: 70-73, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29279089

RESUMO

Neospora caninum is one of the main agents that causes abortions in cattle worldwide. However, little is known about the pathogenesis of neosporosis in small ruminants, especially goats. Gerbils (Meriones unguiculatus) have been used as a model for neosporosis, and this species is highly susceptible to infection by bovine N. caninum strains. The present study aimed to evaluate the susceptibility of gerbils to a N. caninum isolate from goats. The placentas were obtained from naturally infected goats, that presented with mild to severe lymphoplasmacytic and histiocytic infiltrate, foci of necrosis, calcification and protozoan-like structures. Immunosuppressed gerbils bioassayed with N. caninum-infected placental tissues showed severe neurological signs. Microscopic lesions in these gerbils were characterized by encephalitis, myocarditis, myositis and pancreatitis. These lesions were often associated with a small to moderate number of N. caninum tachyzoites, confirmed by immunohistochemistry and PCR. This is the first report showing that goat N. caninum strains could infect immunocompetent gerbils and cause severe lesions and clinical signs in immunosuppressed gerbils.


Assuntos
Bioensaio , Coccidiose/parasitologia , Coccidiose/transmissão , Gerbillinae/parasitologia , Doenças das Cabras/parasitologia , Neospora/fisiologia , Animais , Coccidiose/imunologia , Coccidiose/patologia , Modelos Animais de Doenças , Feminino , Gerbillinae/imunologia , Doenças das Cabras/transmissão , Cabras , Imuno-Histoquímica , Neospora/genética , Placenta/parasitologia , Reação em Cadeia da Polimerase , Gravidez
17.
Artigo em Inglês | MEDLINE | ID: mdl-31014740

RESUMO

Neospora caninum is a tissue cyst-forming coccidium capable of causing spinal cord or skeletal muscle disease in dogs. Infected bitches can transmit the parasite to their pups in utero. Seroprevalence of N. caninum was studied in naturally-infected, privately owned Bernese Mountain dogs, using antibody detection via an indirect fluorescent antibody test (IFAT) to identify infected individuals. A retrospective study was undertaken on available dogs from 14 litters. Five of eight dams tested seropositive. The index case was a bitch with a titre of 1:3200 by IFAT. Only one offspring from her first litter was seropositive. The frequency of putative congenital transmission in the breeding kennel was variable. Our results reiterate the importance of serological testing of all dams and littermates in a breeding kennel when clinical neosporosis is suspected in neonatal puppies.


Assuntos
Anticorpos Antiprotozoários/sangue , Coccidiose/veterinária , Doenças do Cão/transmissão , Transmissão Vertical de Doença Infecciosa/veterinária , Complicações Parasitárias na Gravidez/veterinária , Animais , Coccidiose/transmissão , Doenças do Cão/parasitologia , Cães/parasitologia , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Masculino , Neospora , Gravidez , Estudos Retrospectivos , Estudos Soroepidemiológicos
18.
Vet Parasitol ; 248: 84-89, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29173547

RESUMO

Bovine besnoitiosis, caused by Besnoitia besnoiti, is an economically important disease of cattle in many countries but its transmission remains a mystery. Wild felids are suspected to be its definitive hosts. The domestic cat (Felis catus) is known experimental definitive host for Besnoitia species of rodents. Here, we report for Besnoitia darlingi the first identification of a natural definitive host, the bobcat (Lynx rufus). Oocysts resembling Toxoplasma gondii (unsporulated; 10.9±0.8×12.1±0.2µm; n=5) were detected microscopically in the feces of two of 25 free ranging wild bobcats from Mississippi, USA. After detailed investigation, we identified these oocysts as B. darlingi and not T. gondii. The IFN-γ gene knockout (KO) mice fed oocysts from bobcats died of acute besnoitiosis and tachyzoites were found in their tissues. Oocysts were also mildly pathogenic to outbred Swiss Webster mice (SW) (Mus musculus). The SW mice fed oocysts became ill but generally survived and developed characteristic thick-walled Besnoitia tissue cysts in their tongue and heart muscles and brains. Two laboratory-raised domestic cats (Felis catus) excreted B. darlingi oocysts after ingesting murine tissues infected with bobcat-derived oocysts. The parasite was successfully cultivated in African green monkey kidney fibroblast cells (CV-1 cell line) seeded with infected murine tissue homogenate. The multilocus PCR-DNA sequencing (18S rDNA, 28S rDNA, and ITS-1) from culture-derived tachyzoites confirmed the parasite as B. darlingi. Our results suggest that bobcats may be an important link in the sylvatic cycle of Besnoitia species and bioassay or molecular tests are needed to differentiate Toxoplasma gondii-like oocysts in feces of felids, both domestic and wild cats.


Assuntos
Doenças do Gato/transmissão , Coccidiose/veterinária , Didelphis , Reservatórios de Doenças/parasitologia , Lynx , Sarcocystidae/fisiologia , Animais , Doenças do Gato/parasitologia , Gatos , Linhagem Celular , Chlorocebus aethiops , Coccidiose/parasitologia , Coccidiose/transmissão , Fezes/parasitologia , Feminino , Masculino , Camundongos , Mississippi , Oocistos/isolamento & purificação
19.
Parasit Vectors ; 10(1): 503, 2017 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-29052521

RESUMO

BACKGROUND: Canids are definitive hosts of the apicomplexan parasite Neospora caninum, the leading cause of abortion in cattle worldwide. For horizontal transmission from canids to occur, oocysts of N. caninum must be shed by the definitive host into the environment of susceptible intermediate hosts such as cattle. The purpose of this study was to determine the prevalence of N. caninum in canids in Victoria, Australia's leading dairy producing state. RESULTS: Neospora-like oocysts were observed in 8% (18/234) of faecal samples from wild dogs, domestic dogs and red foxes from Victoria, Australia. However, none tested positive for N. caninum DNA using a quantitative PCR. In a separate sample population, blood sera from 483 domestic dogs were tested for anti-N. caninum antibodies using competitive ELISA. A subset of cELISA samples were re-tested using indirect fluorescence antibody test (IFAT). A seroprevalence of 29.8% (144/483; 95% CI: 11.7-47.8%) was calculated when using cELISA; whereas it was 32.9% (27/80; 95% CI: 15.8-51.8%) using IFAT. Potential risk factors were evaluated using univariable analyses and then assessed in separate multivariable models. Using 'aged' dogs as a reference, the seroprevalence of 'adolescent' and 'adult' dogs was 88% (P = 0.05) and 91% (P = 0.08), respectively, indicating seroprevalence increases with age. There was a 19% higher likelihood of infection in rural locations (P = 0.10) relative to urban areas. Jack Russell Terriers had a 22% higher risk of a cELISA-positive result (P = 0.05) regardless of geographical location, age or sex. CONCLUSION: These results demonstrate that exposure to N. caninum in domestic dogs is widespread in Victoria, although faecal oocyst shedding is infrequent. Our results indicate increased N. caninum seroprevalance status in dogs over the past two decades. The results imply that dogs get either exposed to the infected meat more frequently or that vertical dam to foetus transmission is more frequent than previously thought. Our study calls for re-evaluation of historical N. caninum seroprevalance studies, because the attitude to dog diet changes.


Assuntos
Anticorpos Antiprotozoários/sangue , Coccidiose/veterinária , Doenças do Cão/epidemiologia , Neospora/imunologia , Animais , Animais Selvagens/parasitologia , Bovinos , Coccidiose/epidemiologia , Coccidiose/imunologia , Coccidiose/transmissão , Doenças do Cão/imunologia , Doenças do Cão/parasitologia , Doenças do Cão/transmissão , Cães , Ensaio de Imunoadsorção Enzimática , Fezes/parasitologia , Feminino , Raposas/parasitologia , Masculino , Neospora/genética , Neospora/isolamento & purificação , Oocistos/genética , Oocistos/isolamento & purificação , Reação em Cadeia da Polimerase , Gravidez , População Rural , Estudos Soroepidemiológicos , Fatores de Tempo
20.
Rev Bras Parasitol Vet ; 26(3): 253-279, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28876360

RESUMO

Neospora caninum is protozoan parasite with domestic and wild dogs, coyotes and grey wolves as the definitive hosts and many warm-blooded animals as intermediate hosts. It was cultivated and named in 1988. Neosporosis is a major disease of cattle and has no public health significance. Since 1990's N. caninum has emerged as a major cause of abortion in cattle worldwide, including in Brazil. N. caninum also causes clinical infections in several other animal species. Considerable progress has been made in understanding the biology of N. caninum and there are more than 200 papers on this subject from Brazil. However, most of the reports on neosporosis from Brazil are serological surveys. Overall, little is known of clinical neosporosis in Brazil, particularly cattle. The few reports pertain to sporadic cases of abortion with no information on epidemics or storms of abortion. The objective of the present review is to summarize all reports from Brazil and suggest topic for further research, including prevalence of N. caninum oocysts in soil or in canine feces, and determining if there are additional definitive hosts, other than the domestic dog. There is need for a national survey in cattle using defined parameters. Future researches should focus on molecular characterization of N. caninum strains, possibility of vaccine production and relationship between wildlife and livestock epidemiology.


Assuntos
Coccidiose/veterinária , Neospora/isolamento & purificação , Animais , Animais Domésticos/parasitologia , Animais Selvagens/parasitologia , Brasil , Coccidiose/epidemiologia , Coccidiose/transmissão
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