Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 40
Filtrar
1.
Exp Parasitol ; 199: 40-46, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30840850

RESUMO

Human African trypanosomosis (HAT) and animal African trypanosomosis (AAT) are diseases of economic importance in humans and animals that affect more than 36 African countries. The currently available trypanocidal drugs are associated with side effects, and the parasites are continually developing resistance. Thus, effective and safe drugs are needed for the treatment of HAT and AAT. This study aimed to evaluate the effects of azithromycin (AZM) on Trypanosoma brucei brucei-infected mice. Mice were randomly divided into 7 groups consisting of a vehicle control group, 5 test groups and a diminazene aceturate (DA)-treated group. Mice were treated orally for 7 and 28 days, as short-term and long-term treatments, respectively. Short-term AZM treatment cured 23% (16 of 70) of the overall treated mice whereas long-term treatment resulted in the survival of 70% of the mice in the groups that received AZM at doses of 300 and 400 mg/kg. Trypanosomes treated in vitro with 25 µg/mL of AZM were subjected to transmission electron microscopy, which revealed the presence of increased numbers of glycosomes and acidocalcisomes in comparison to the vehicle group. The current study showed the trypanocidal effect of AZM on T. b. brucei in vivo. The demonstrated efficacy increased with an increase in treatment period and an increased concentration of AZM.


Assuntos
Anti-Infecciosos/administração & dosagem , Azitromicina/administração & dosagem , Trypanosoma brucei brucei/efeitos dos fármacos , Tripanossomíase Africana/tratamento farmacológico , Administração Oral , Animais , Anti-Infecciosos/farmacologia , Anti-Infecciosos/uso terapêutico , Azitromicina/farmacologia , Azitromicina/uso terapêutico , Peso Corporal/efeitos dos fármacos , Feminino , Concentração Inibidora 50 , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Parasitemia/tratamento farmacológico , Distribuição Aleatória , Taxa de Sobrevida , Fatores de Tempo , Trypanosoma brucei brucei/ultraestrutura , Tripanossomíase Africana/mortalidade
2.
Parasitol Res ; 118(6): 1927-1935, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31055671

RESUMO

Trypanosoma (Megatrypanum) theileri is a cosmopolitan, usually non-pathogenic, trypanosome of cattle transmitted by blood-sucking arthropods, mainly tabanid flies. Several T. theileri strains isolated from domestic and wild ruminants via co-culturing with mammalian feeder cells or blood cells have been characterized morphologically and genetically. Here, we cultured a new trypanosome isolate from a Holstein cow in Hokkaido, Japan, and performed morphological and molecular characterization studies. The new isolate (Obihiro strain) was co-cultivated with Madin-Darby bovine kidney (MDBK) cells in GIT medium supplemented with 10% fetal bovine serum. Trypomastigotes and epimastigotes, but not intracellular parasites, were identified in the culture. Analysis of the V7-V8 region of 18S rRNA sequences showed that the Obihiro strain is positioned within the subgenus Megatrypanum. A dendrogram based on whole internal transcribed spacer rDNA sequence showed that the Obihiro strain clustered in the lineage TthII together with the Japanese isolates of T. theileri, Esashi 9, and Esashi 12, and isolates from Zambia and the USA. T. theileri of the KM strain and a T. theileri-like trypanosome isolated from deer (TSD1 strain) clustered in the lineage TthI, separate from the Obihiro strain. Based on a partial cathepsin L-like protein gene analysis, the Obihiro strain clustered with isolates of the TthIIF genotype, which includes T. theileri from Vietnam, Sri Lanka, and Brazil. Our analyses of the T. theileri Obihiro strain provide relevant insights into its genetic diversity in Japanese cattle and corroborate the host specificity of cattle and deer trypanosomes of the subgenus Megatrypanum.


Assuntos
Doenças dos Bovinos/parasitologia , Trypanosoma/classificação , Trypanosoma/genética , Tripanossomíase/veterinária , Animais , Catepsina L/genética , Bovinos , Linhagem Celular , DNA Ribossômico/genética , DNA Espaçador Ribossômico/genética , Cervos/parasitologia , Feminino , Genótipo , Especificidade de Hospedeiro , Japão , Filogenia , RNA Ribossômico 18S/genética , Trypanosoma/isolamento & purificação , Tripanossomíase/parasitologia
3.
Trop Anim Health Prod ; 51(3): 555-563, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30426339

RESUMO

Anthelmintic treatment is the most common way of controlling nematode infections in ruminants even though several countries have reported anthelmintic resistance (AR), resulting in limitation for sustainable small ruminant production. The aim of the present study was to evaluate the knowledge of resource-poor sheep farmers in Limpopo province of South Africa on the use of anthelmintics. A questionnaire regarding helminthosis control practices was administered to small ruminant farmers in five districts of Limpopo province namely Capricorn, Sekhukhune, Waterberg, Vhembe, and Mopani. A total of 77 resource-poor farmers were interviewed between June and August of 2017 using a structured questionnaire with a combination of qualitative and quantitative open-ended questions. The interviewed farmers were divided into three groups based on their farming experience (< 5; 6-10, and ˃ 10 years of farming experience). Limited farming experience was shown as one of the risks, as farmers that owned sheep for less than 10 years could not identify the symptoms of gastrointestinal parasites infection and did not know how nematodes are transmitted to animals. However, no significant difference (p < 0.05) was found to exist between the three groups of farmers in terms of clinical signs identification and correct application of anthelmintics. About 43% of the respondents were unaware of gastrointestinal nematodes (GI) that infect sheep, could not identify the clinical symptoms of gastrointestinal nematodes infection, and only 34% knew how animals become infected. Although 67.5% of farmers mentioned that they never dose their sheep, 32.5% use anthelmintics at varying times in a year. None of the farmers weighed their sheep before dosing them instead visual appraisal of individual weight was the most common means of estimating the anthelmintic dose. The above information is an indication of risks associated with possible occurrence of anthelmintic resistance in the study areas. There is therefore, a need to give training to resource-poor farmers of small stock on proper application of anthelmintic treatment and to educate them on how to prevent development of AR. Future studies on AR should also be conducted in the province in flocks with high-treatment frequencies to establish the occurrence of AR using both in vivo and in vitro methods. The most common risk factor associated with the occurrence of AR in all the five districts of Limpopo province was found to be the use of anthelmintics without weighing the animals to determine the correct dosage.


Assuntos
Anti-Helmínticos/farmacologia , Fazendeiros , Helmintíase Animal/parasitologia , Enteropatias Parasitárias/veterinária , Doenças dos Ovinos/parasitologia , Animais , Resistência a Medicamentos , Helmintíase Animal/economia , Helmintíase Animal/epidemiologia , Enteropatias Parasitárias/economia , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Fatores de Risco , Ovinos , Doenças dos Ovinos/epidemiologia , África do Sul/epidemiologia , Inquéritos e Questionários
4.
Parasitology ; 144(9): 1162-1178, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28502276

RESUMO

Tabanids are haematophagous flies feeding on livestock and wildlife. In the absence of information on the relationship of tabanid flies and protozoan parasites in South Africa and Zambia, the current study was aimed at characterizing tabanid flies collected in these two countries as well as detecting protozoan parasites they are harbouring. A total of 527 tabanid flies were collected whereby 70·2% were from South Africa and 29·8% were from Zambia. Morphological analysis revealed a total of five different genera collected from the sampled areas namely: Ancala, Atylotus, Haematopota, Philoliche and Tabanus. DNA extracted from South African Tabanus par and Tabanus taeniola tested positive for the presence of Trypanosoma congolense (Savannah) and Trypanosoma theileri whilst one member from T. par was positive for Trypanosoma brucei species. DNA extracted from Zambian tabanid flies tested positive for the presence of Besnoitia species at 1·27% (2/157), Babesia bigemina 5·73% (9/157), Theileria parva 30·11% (30/157) and 9·82% (14/157) for Trypanosoma evansi. This study is the first to report on relationship of Babesia and Theileria parasites with tabanid flies. Further investigations are required to determine the role of tabanids in transmission of the detected protozoan parasites in livestock and wildlife in South Africa and Zambia.


Assuntos
Babesia/isolamento & purificação , Dípteros/parasitologia , Insetos Vetores/parasitologia , Sarcocystidae/isolamento & purificação , Theileria/isolamento & purificação , Trypanosoma/isolamento & purificação , Animais , Babesia/genética , Dípteros/classificação , Insetos Vetores/classificação , Sarcocystidae/genética , África do Sul , Theileria/genética , Trypanosoma/genética , Zâmbia
5.
Parasitology ; 141(3): 411-24, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24229841

RESUMO

Strict control measures apply to movement of buffalo in South Africa including testing for Theileria parva, the causative agent of Corridor disease in cattle. The official test is a real-time hybridization PCR assay that amplifies the 18S rRNA V4 hyper-variable region of T. parva, T. sp. (buffalo) and T. sp. (bougasvlei). Mixed infections with the latter organisms affect diagnostic sensitivity due to PCR suppression. While the incidence of mixed infections in the Corridor disease endemic region of South Africa is significant, little information is available on the specific distribution and prevalence of T. sp. (buffalo) and T. sp. (bougasvlei). Specific real-time PCR assays were developed and a total of 1211 samples known to harbour these parasites were screened. Both parasites are widely distributed in southern Africa and the incidence of mixed infections with T. parva within the endemic region is similar (∼25-50%). However, a significant discrepancy exists in regard to mixed infections of T. sp. (buffalo) and T. sp. (bougasvlei) (∼10%). Evidence for speciation between T. sp. (buffalo) and T. sp. (bougasvlei) is supported by phylogenetic analysis of the COI gene, and their designation as different species. This suggests mutual exclusion of parasites and the possibility of hybrid sterility in cases of mixed infections.


Assuntos
Búfalos/parasitologia , Doenças dos Bovinos/epidemiologia , Theileria/fisiologia , Theileriose/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Coinfecção , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Demografia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Especiação Genética , Especificidade de Hospedeiro , Incidência , Parasitemia/veterinária , Filogenia , Proteínas de Protozoários/genética , Sensibilidade e Especificidade , África do Sul/epidemiologia , Theileria/classificação , Theileria/genética , Theileria/isolamento & purificação , Theileria parva/classificação , Theileria parva/genética , Theileria parva/isolamento & purificação , Theileria parva/fisiologia , Theileriose/parasitologia
6.
Microorganisms ; 11(6)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37374941

RESUMO

Houseflies are alleged reservoirs as well as vectors of human and animal pathogens, including bacteria, because they frequently have contact with animal excreta and decaying organic substances. The rapid adaptation process of ingested microbes in the insect gut may involve gene transfer, including antibiotic resistance determinants among different bacterial strains. Six hundred and fifty-seven (n = 657) houseflies were collected from hospices and were identified morphologically and genetically using the 16S rRNA, CO1, and ITS2 barcoding genes. This study also characterized the bacterial communities harboured by the captured houseflies using 16S rRNA metabarcoding on the next-generation sequencing (NGS) platform and further sought to detect antibiotic resistance traits by using gene-specific PCR assays. Generated sequences for the targeted gene fragments matched with Musca domestica and all the sequences were deposited to the GenBank database. The 16S rRNA metabarcoding analysis revealed that the most abundant phyla detected with variable abundance observed among all the houseflies were Proteobacteria, followed by Firmicutes, and Bacteroidetes. Furthermore, the NGS data revealed the presence of multiple bacterial genera, including Providencia, Enterobacter, Dysgonomonas, Escherichia-Shigella, Klebsiella, Pseudomonas, and Streptococcus, which are known to harbour potentially pathogenic species of animals and humans. Antibiotic resistance genes detected from the housefly DNA in this study included ermB, tetA, blaSHV, and blaTEM. Moreover, these genes are associated with resistance to erythromycin, tetracycline, and beta-lactams antibiotics, respectively. The presence of bacterial pathogens and the detection of antibiotic resistance genes from the houseflies collected from the hospices indicates the possible health risk to patients in hospices and the surrounding community. Therefore, it is imperative to keep high standards of hygiene, food preparation, safety, and control of houseflies in hospices.

7.
Vet Parasitol ; 320: 109978, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37364501

RESUMO

Trematodiases are diseases caused by snail-borne trematode parasites that infect both animals and humans. Fascioliasis, schistosomiasis and paramphistomosis are some of these diseases and they affect millions of livestock, leading to significant economic losses. The aim of the study was to document freshwater snails occurring in selected study sites in the Free State and Gauteng provinces as well as identify and detect larval trematodes that they harbour. Samples were collected from a total of five study sites within two provinces of South Africa. Morphological features were used to identify snail species and were further confirmed genetically by polymerase chain reaction (PCR), sequencing and phylogenetic analysis. The larval trematodes were also detected by PCR, PCR-Restriction Length Fragment Polymorphism (PCR-RLFP), sequencing and phylogenetic analysis. A total of 887 freshwater snails were collected from Free State (n = 343) and Gauteng (n = 544). Five different genera of snails as well as species in the Succineidae family were documented. The snails in descending order of abundance were identified as: Physa (P.) spp. (51%), Succineidae spp. (20%), Galba (G.) truncatula (12%), Pseudosuccinea (Ps.) columella (10%), Planorbella (Pl.) duryi (6%) and Bulinus (B.) truncatus (1%). Approximately 272 DNA pools were created for genetic identification of snails and detection of trematode parasites. Schistosoma species were not detected from any of the snail species. A total prevalence of 46% was obtained for Fasciola hepatica in the identified snail species across all study sites. Overall, the highest prevalence of F. hepatica was obtained in Physa species (24%), whilst the lowest was observed in B. truncatus snails (1%). Forty three percent (43%) of the snail samples were PCR positive for Paramphistomum DNA. This is the first report of P. mexicana in South Africa. Fasciola hepatica was confirmed from all obtained snail species per study site. This is the first reported detection of F. hepatica in Pl. duryi and P. mexicana snails as well as the first confirmation of natural infection from P. acuta in South Africa.


Assuntos
Fasciola hepatica , Fasciola , Paramphistomatidae , Trematódeos , Infecções por Trematódeos , Humanos , Animais , Fasciola/genética , Paramphistomatidae/genética , África do Sul/epidemiologia , Filogenia , Fasciola hepatica/genética , Infecções por Trematódeos/epidemiologia , Infecções por Trematódeos/veterinária , Infecções por Trematódeos/parasitologia , Schistosoma/genética , Água Doce/parasitologia , Larva
8.
Vet Med Sci ; 8(2): 827-844, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33955703

RESUMO

Housefly (Musca domestica) is an excellent candidate for the distribution of susceptible and resistant bacterial strains that potentially threaten public health. To date, there is a paucity of information on the global distribution of pathogenic bacteria of medical and veterinary importance from diverse environmental settings. Therefore, this study was undertaken to conduct a systemic review and meta-analysis to estimate occurrence of various bacterial species of medical and veterinary importance harboured by houseflies around the world. Published articles from 1980 to 2020 were retrieved from electronic databases and assessed for eligibility according to Preferred Reporting Items for Systemic Reviews and Meta-Analysis guidelines. Seventy-eight studies were included in the review with only 44 studies being eligible for meta-analysis. Results indicated that eligible studies used in this review were from four continents, i.e., Asia (47.4%) America (23.1%), Africa (20.5%) and Europe (8.9%). The majority of the studies (56.4%) used the culture method for the identification of bacterial pathogens, while 30.7% used both culture and PCR techniques. For meta-analysis, we focused on five pathogenic bacterial species including Escherichia coli, Enterococcus faecium, Klebsiella pneumoniae, Pseudomonas aeruginosa and Staphylococcus aureus. High heterogeneity was found among studies investigating different pathogens including E. coli (Q = 10,739.55; I2  = 99.60; Q-p 0.0001), E. faecium (Q = 317.61; I2  = 86.46; Q-p < 0.0001), K. pneumonia (Q = 1,576.61; I2  = 97.27; Q-p < 0.0001), S. aureus (Q = 2,439.12; I2  = 98.24; Q-p < 0.0001) and P. aeruginosa (Q = 1,283.0; I2  = 96.65; Q-p < 0.0001). Furthermore, it was observed that houseflies carried a considerable number of susceptible and antibiotic-resistant bacterial strains that pose considerable threats to public health. Findings from this study have provided more insight on the vectoral potential of houseflies in the transmission of significant bacterial pathogens from different regions across the world. Further investigation is required to quantify the bacterial contamination and dissemination by houseflies.


Assuntos
Moscas Domésticas , Animais , Antibacterianos , Bactérias , Escherichia coli , Humanos , Staphylococcus aureus
9.
Microorganisms ; 10(2)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35208768

RESUMO

The rapid growth of multidrug-resistant Salmonella is a global public health concern. The aim of this study was to detect integrons, colistin and ß-lactamase resistance genes in Salmonella enteritidis and typhimurium. A total of 63 isolates of S. enteritidis (n = 18) and S. typhimurium (n = 45) from fecal samples of layers and rats at chicken farms were screened for antibiotic resistant genes. Conventional PCR was performed for the detection of integrons (classes 1, 2, and 3), colistin (mcr-1-5) and ß-lactamase (blaCTX-M, blaCTX-M-1, blaCTX-M-2, blaCTX-M-9, blaCTX-M-15, blaTEM, blaSHV, and blaOXA) resistant genes. Of these isolates, 77% and 27% of S. typhimurium and S. enteritidis harboured the mcr-4 encoded gene for colistin, respectively. The prevalence of class 1 integrons for S. typhimurium and S. enteritidis was 100% for each serovar, while for class 2 integrons of S. typhimurium and S. enteritidis it was 49% and 33% respectively, while class 3 integron genes was not detected. Our study also detected high levels of ß-lactamase encoding genes (bla gene), namely blaCTX-M, blaCTX-M-1, blaCTX-M-9 and blaTEM from both S. typhimurium and S. enteritidis. This, to our knowledge, is the first report of mcr-4 resistance gene detection in Salmonella serovars in South Africa. This study also highlights the importance of controlling rats at poultry farms in order to reduce the risk of transmission of antibiotic resistance to chickens and eventually to humans.

10.
Vet Parasitol Reg Stud Reports ; 36: 100798, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36436906

RESUMO

Free-range chickens are an integral part of poultry production in many developing countries. In the Mountain Kingdom of Lesotho, the majority of the population own free-range chickens, which serve a variety of purposes including being a source of meat, eggs and use for cultural rituals amongst others. However, there is lack of scientific studies on occurrence of parasitic infections on free-range chickens in Lesotho. The aim of this study was to document common gastrointestinal parasites infecting free-range chickens in four villages of Mafeteng District in Lesotho. A total number of 462 pooled faecal samples were collected from various households in HaKubutu (n = 114), HaMatjeka (n = 120), HaMpalipali (n = 120) and Thabang Villages (n = 108) which were subjected to microscopic examination using McMaster technique. The prevalence of gastrointestinal parasite infection was as follows: Eimeria tenella (12.8%), Ascaridia galli (10.4%) and Heterakis gallinarum (5%). The prevalence for H. gallinarum and Ascaridia galli were comparatively higher during the hot-wet season (7.1% and 2.8% respectively) than the cold-dry season (3.2% and 1.9% respectively) and varied significantly (P < 0.05). For E. tenella, the oocysts per gram were slightly higher in the cold-dry season than the hot-wet season. Polymerase chain reaction only amplified DNA from six (29%) adult A. galli worms of which two amplicons were successfully sequenced. The obtained cytochrome C oxidase subunit 1 partial gene sequences displayed 98-100% identity with South African A. galli isolates. This is the first scientific study on prevalence and molecular characterization of nematodes and coccidia species infecting free-range village chickens in Lesotho. The findings can be used to review management of gastrointestinal nematodes and protozoal parasites of free-range chickens in Lesotho.


Assuntos
Coccídios , Parasitos , Animais , Galinhas , Lesoto/epidemiologia , Ascaridia
11.
Vet Parasitol Reg Stud Reports ; 29: 100691, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35256119

RESUMO

A total of 3311 tick specimens were randomly collected from domestic animals including cattle, sheep, goats, horses, donkeys, and dogs from Lesotho districts namely, Berea, Butha-Buthe, Leribe, Mafeteng, Maseru, Mohale's Hoek, Mokhotlong, Qacha's Nek, Quthing and Thaba Tseka. Tick species were identified morphologically and verified by amplification and sequencing of the CO1 and 18S rRNA genes. Nine species were identified under different genera namely, Haemaphysalis elliptica 0.1% (n = 2), Hyalomma rufipes 2.6% (n = 87), Hy. truncatum 1.2% (n = 41), Otobius megnini 13.6% (n = 451), Rhipicephalus appendiculatus 0.1% (n = 3), Rhipicephalus decoloratus 9.3% (n = 308), Rhipicephalus evertsi evertsi 65.1% (n = 2156), Rhipicephalus glabroscutatum 1.3% (n = 43) and Rhipicephalus microplus 6.6% (n = 220). There was a significant difference at p = 6.2E-06 (ꭓ2 = 1.923, df = 7) in the distribution of tick species and their abundance p = 0.04 (ꭓ2 = 1.923, df = 7) from each population. The CO1 and 18S rRNA sequences matched the morphological determinations on the NCBI database and clustered with relevant species on the phylogenetic tree. Genetic analysis of CO1 and 18S rRNA provided very strong support for monophyly of the Rhipicephalinae and Ornithodorinae complexes. Both CO1 and 18S rRNA are useful genetic markers for the specific and generic characterization of tick species in Lesotho and elsewhere. This is the first scientific publication of tick species occurring in Lesotho.


Assuntos
Doenças do Cão , Doenças das Cabras , Doenças dos Cavalos , Ixodidae , Rhipicephalus , Doenças dos Ovinos , Infestações por Carrapato , Animais , Animais Domésticos , Bovinos , Cães , Cavalos , Lesoto , Filogenia , RNA Ribossômico 18S/genética , Rhipicephalus/genética , Ovinos , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterinária
12.
Parasitology ; 138(7): 884-95, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21524322

RESUMO

Buffalo-adapted Theileria parva causes Corridor disease in cattle. Strict control measures therefore apply to the movement of buffalo in South Africa and include mandatory testing of buffalo for the presence of T. parva. The official test is a real-time hybridization PCR assay that amplifies the V4 hypervariable region of the 18S rRNA gene of T. parva, T. sp. (buffalo) and T. sp. (bougasvlei). The effect that mixed T. parva and T. sp. (buffalo)-like infections have on accurate T. parva diagnosis was investigated in this study. In vitro mixed infection simulations indicated PCR signal suppression at 100 to 1000-fold T. sp. (buffalo) excess at low T. parva parasitaemia. Suppression of PCR signal was found in field buffalo with mixed infections. The T. parva-positive status of these cases was confirmed by selective suppression of T. sp. (buffalo) amplification using a locked nucleic acid clamp and independent assays based on the p67, p104 and Tpr genes. The incidence of mixed infections in the Corridor disease endemic region of South Africa is significant, while the prevalence in buffalo outside the endemic area is currently low. A predicted increase of T. sp. (buffalo)-like infections can affect future diagnoses where mixed infections occur, prompting the need for improvements in current diagnostics.


Assuntos
Búfalos/parasitologia , Parasitemia/veterinária , Theileria parva/fisiologia , Theileriose/diagnóstico , Theileriose/parasitologia , Animais , Coinfecção/diagnóstico , Coinfecção/epidemiologia , Coinfecção/parasitologia , Genes de Protozoários/genética , Marcadores Genéticos/genética , Incidência , Parasitemia/epidemiologia , Prevalência , RNA Ribossômico 18S/genética , África do Sul/epidemiologia , Theileria parva/genética
13.
Parasitology ; 138(14): 1935-44, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21902875

RESUMO

Corridor disease is an acute, fatal disease of cattle caused by buffalo-adapted Theileria parva. This is a nationally controlled disease in South Africa and strict control measures apply for the movement of buffalo, which includes mandatory testing for the presence of T. parva and other controlled diseases. Accurate diagnosis of the T. parva carrier state in buffalo using the official real-time hybridization PCR assay (Sibeko et al. 2008), has been shown to be affected by concurrent infection with T. sp. (buffalo)-like parasites. We describe the Hybrid II assay, a real-time hybridization PCR method, which compares well with the official hybridization assay in terms of specificity and sensitivity. It is, however, not influenced by mixed infections of T. sp. (buffalo)-like parasites and is as such a significant improvement on the current hybridization assay.


Assuntos
Búfalos/parasitologia , Hibridização de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Theileria parva/isolamento & purificação , Theileriose/diagnóstico , Animais , Sequência de Bases , Portador Sadio/veterinária , Bovinos , Coinfecção/veterinária , Dados de Sequência Molecular , Sensibilidade e Especificidade , Alinhamento de Sequência/veterinária , África do Sul , Theileria parva/genética , Theileriose/parasitologia
14.
Parasitol Res ; 109(6): 1735-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21739311

RESUMO

This study compared the prevalence of trypanosome infections estimated by PFR-loop-mediated isothermal amplification (LAMP) with conventional polymerase chain reaction (PCR) tests. One hundred forty eight cattle blood samples were collected from Robanda village, Mara region, Tanzania in April 2008. In conventional PCR, four sets of primers, specific for the detection of Trypanosoma sp., Trypanosoma brucei rhodesiense, Trypanosoma vivax, and Trypanozoon, as well as a modified LAMP were used. Conventional PCR detected no infection or up to 8, 1, and 3 infections with Trypanosoma congolense savannah, Trypanozoon, and T. vivax, respectively, whereas LAMP detected additional 44 Trypanozoon positive cases. Our results clearly indicate that the prevalence of Trypanozoon spp. in cattle in Robanda village estimated by PFR-LAMP (30.4%) was significantly higher than the estimates by PCR assays (0.6-2%). As such, future studies should target epidemiological surveys of Trypanozoon and T. brucei rhodesiense infections in possible reservoir animals by LAMP to further elucidate the actual prevalence of these parasites.


Assuntos
Técnicas de Amplificação de Ácido Nucleico , Reação em Cadeia da Polimerase/métodos , Trypanosoma/isolamento & purificação , Tripanossomíase Africana/veterinária , Tripanossomíase Bovina/epidemiologia , Animais , Bovinos , Primers do DNA , Feminino , Masculino , Prevalência , Tanzânia/epidemiologia , Trypanosoma/genética , Tripanossomíase Africana/epidemiologia , Tripanossomíase Africana/parasitologia , Tripanossomíase Bovina/parasitologia
15.
Vet World ; 14(11): 2929-2935, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35017840

RESUMO

BACKGROUND AND AIM: Infections with Campylobacter species have gained recognition as the most frequent cause of foodborne gastroenteritis globally. Their significance in South Africa is still an area of study interest. This study was, therefore, carried out to determine the occurrence of Campylobacter species in chickens from North West Province of South Africa as well as their antibiotic sensitivity status. MATERIALS AND METHODS: A total of 2400 chicken fecal samples were collected and pooled to a total of 480 samples from five registered active poultry abattoirs in the Ngaka Modiri Molema District of North West Province, South Africa. Polymerase chain reaction (PCR) was used for the detection of Campylobacter spp. targeting the 16S rRNA gene while antibiotic sensitivity was determined using disk diffusion inhibition test. RESULTS: After isolation, a total of 26 samples were confirmed to be harboring Campylobacter jejuni by PCR and sequencing. C. jejuni was found to be the only isolate detected in all the fecal samples tested. The study further demonstrated that C. jejuni infections were highest in the summer season (3%) followed by autumn and winter at 1%, while there were none detected in the spring. The isolated C. jejuni-positive samples on disk diffusion inhibition test displayed resistance to nalidixic acid, tetracycline, erythromycin, and ciprofloxacin at 98%, 80%, 83%, and 21%, respectively. CONCLUSION: C. jejuni isolated in this study is known to cause disease in humans, and thus its occurrence requires application of "One Health" strategy to reduce the spread of this zoonotic pathogen in South Africa.

16.
Vet World ; 14(2): 302-313, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33776295

RESUMO

BACKGROUND AND AIM: Previous studies recorded the prevalence of gastrointestinal nematodes (GIN) in Limpopo Province. However, the studies did not address the seasonal patterns of infection and did not cover all districts of Limpopo Province, namely; Capricorn, Sekhukhune, Waterberg, Mopani, and Vhembe. It is, therefore, important to provide up to date information on the prevalence and seasonal occurrence data of GIN in all districts of Limpopo province. The present study was conducted to determine the occurrence of anthelmintic resistance (AR) and document the prevalence of GIN infecting sheep in five districts of Limpopo Province, South Africa. MATERIALS AND METHODS: Forty animals in each district were used for fecal egg count reduction test (FECRT) to determine AR against ivermectin (0.2 mg/kg), levamisole (LEV) (5 mg/kg), and albendazole (7.5 mg/kg). Egg hatch test (EHT) was used to determine AR against thiabendazole (TBZ) and micro-agar larval development test (MALDT) was used for both TBZ and LEV. Naturally, infected sheep (n=780) were sampled for prevalence across five districts of Limpopo. FAMACHA© eye-color score estimations were also performed for each study animal. RESULTS: FECRT showed occurrence of AR in most of the districts and a few with suspected resistance. EHT results showed AR development against TBZ for all districts, while the MALDT showed no AR against LEV in all districts, but detected AR against TBZ in Sekhukhune, Capricorn, and Waterberg. Haemonchus contortus was the most resistant species. A high nematode prevalence (88-100%) and 1210-1861 eggs per gram (EPG) was observed in all districts during the hot wet season, decreasing to 75-80% (453-1202 EPG) during the cold dry season. The sheep revealed a FAMACHA© mean score of 3, indicating mild anemia during the hot wet season except for Vhembe district that revealed a FAMACHA© mean score of 4 during the hot wet season, indicating anemia. CONCLUSION: AR recorded in Limpopo Province may be due to under-dosing caused by lack of weighing equipment and high treatment frequencies due to lack of proper training on anthelmintic use. The detection of AR in Limpopo is an important finding because it will help in outlining effective management systems against GIN.

17.
Open Life Sci ; 16(1): 800-808, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34458582

RESUMO

Mastitis is a cow disease usually signalized by irritation, swelling, and soreness of the udder. It is characterized by physical, chemical, and biological changes in the udder and milk. The aim of this study was to detect and characterize pathogens causing subclinical mastitis (SCM) from the milk of dairy cows of small-scale farmers through culture and molecular techniques. Milk was collected from 32 cows belonging to 8 small-scale farmers around Harrismith District, South Africa. The results showed that screening of SCM by California mastitis test and somatic cell counts (SCC) was 21.87 and 25%, respectively. Culture methods revealed the presence of Staphylococcus aureus at 93% followed by Streptococci spp. and Escherichia coli at 36.4 and 13.3%, respectively. The PCR could only detect E. coli, while single-molecule real-time sequencing showed a total of 2 phyla, 5 families, 7 genera, and 131 species. Clostridiaceae was the most abundant family, while Romboutsia was the most abundant genus followed by Turicibacter spp. The present study has documented the occurrence of SCM causing pathogens in milk collected from cows of small-scale farmers in Harrismith, indicating that SCM may be present at higher levels than expected.

18.
Pathogens ; 10(9)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34578218

RESUMO

Tick-borne diseases (TBDs) hamper the growth of the livestock sector and impose major constraints for the health and management of domestic animals in the tropic and subtropical regions globally. Currently, there is no scientific report on the presence of zoonotic pathogens transmitted by tick species in Lesotho. This study aimed to identify zoonotic tick-borne pathogens of economic importance from ticks infesting domestic animals in Lesotho using molecular techniques. A total of 322 tick DNA pools were subjected to PCR screening for the presence of zoonotic pathogens and sequenced. The overall prevalence of Anaplasma spp. was 35% (113/322), with a 100% infection rate in Rhipicephalus microplus, followed by R. evertsi evertsi (92%), Hyalomma rufipes and Otobius megnini sharing 50% and the lowest infection rate was observed in R. decoloratus with 40%. The prevalence of Coxiella burnetii, a gram-negative pleomorphic etiological agent of Query fever (Q fever), was 1% (2/322) for all screened samples, with 20% of R. decoloratus and 1% of R. e. evertsi infected. Rickettsia africae was detected from Hyalomma rufipes with a 70% prevalence. This study provides a baseline knowledge of tick-borne pathogens of medical and veterinary importance in Lesotho and raises awareness of the prevalence of such diseases within the tourism sector as they are mostly affected.

19.
J S Afr Vet Assoc ; 91(0): e1-e11, 2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32787418

RESUMO

This study investigated the occurrence and phylogenetic relationship of protozoan parasites and Ehrlichia infecting domestic animals from three municipalities in uMkhanyakude district of KwaZulu-Natal province, South Africa. A total of 208 blood samples collected from clinically healthy cattle, sheep, goats and dogs from uMkhanyakude district were examined by polymerase chain reaction (PCR) assays, using either genus or species-specific primers to determine the occurrence and phylogenetic relationship of various protozoan parasites and Ehrlichia of veterinary importance. A total of 5/109 (4.6%) cattle were PCR-positive for the presence of Toxoplasma gondii, 33/109 (30.3%) for Babesia bovis, 24/109 (22.02%) for Babesia bigemina and 20/109 (18.3%) for Trypanosoma sp., while 3/10 (30%) of sheep were PCR-positive for Theileria ovis and none of the goats were positive for any of the detected pathogens. The co-infection of 4/109 (3.7%) B. bovis and B. bigemina was detected in cattle. Only Ehrlichia canis was detected in dogs with infection rate of 20/48 (41.7%). Sequences of PCR-positive isolates (B. bovis, B. bigemina, E. canis, T. ovis and T. gondii) showed that they were closely related to their relevant species from various countries. These findings have expanded our knowledge about the prevalence and phylogenetic similarity between protozoan parasites and Ehrlichia isolates of South African origin. To date, this is the first study in South Africa to detect T. gondii infections from cattle blood using PCR.


Assuntos
Babesiose/parasitologia , Coinfecção/veterinária , Ehrlichiose/veterinária , Theileriose/parasitologia , Toxoplasmose Animal/parasitologia , Tripanossomíase/veterinária , Animais , Babesia/classificação , Babesia/isolamento & purificação , Babesiose/microbiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/parasitologia , Coinfecção/microbiologia , Coinfecção/parasitologia , Doenças do Cão/epidemiologia , Doenças do Cão/microbiologia , Doenças do Cão/parasitologia , Cães , Ehrlichia canis/isolamento & purificação , Ehrlichiose/microbiologia , Ehrlichiose/parasitologia , Doenças das Cabras/epidemiologia , Doenças das Cabras/microbiologia , Doenças das Cabras/parasitologia , Cabras , Prevalência , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/microbiologia , Doenças dos Ovinos/parasitologia , África do Sul/epidemiologia , Theileria/isolamento & purificação , Theileriose/microbiologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/microbiologia , Trypanosoma/classificação , Trypanosoma/isolamento & purificação , Tripanossomíase/microbiologia , Tripanossomíase/parasitologia
20.
Int J Parasitol Parasites Wildl ; 13: 98-105, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32983863

RESUMO

The National Zoological Gardens (NZG) is a facility of the South African National Biodiversity Institute (SANBI) and the largest zoo in southern Africa. Among the 9000 captive animals kept by the NZG, is the endangered African penguin (Spheniscus demersus). There have been several post-mortem reports on deaths of penguins in the NZG due to haemosporidian infections, however, the haemosporidian lineages involved and possible insect vector are unknown. Haemosporidians are apicomplexan parasites that infect vertebrates through blood-sucking dipteran insects. Therefore, the current study aimed to identify mosquitoes that are potential vectors found within the African penguin enclosure as well as to detect the haemosporidian parasites from these insects using nested-PCR and real-time PCR (qPCR) analyses. Mosquito samples were collected using an overnight UV-light trap setup for 3 months. From the 65 pooled samples representing 325 mosquitoes, morphological and molecular analysis showed that Culex pipiens (52.31%) was the dominant species followed by Cx. t heileri (30.77%) and Cx. quinquefasciatus (16.92%). Nested-PCR detected parasite DNA of Leucocytozoon sp. and Plasmodium sp. The Cx. pipiens had the highest minimum infection rate (MIR) of 5.88% by nested-PCR and 9.41% by qPCR whilst Cx. quinquefasciatus had MIR of 3.64% in both assays and no haemosporidian parasites were detected from Cx. t heileri. One Cx. pipiens sample had a co-infection of both Plasmodium sp. and Leucocytozoon sp. detected by nested-PCR. These findings suggest that effective control measures for blood-sucking dipteran insects is required at the NZG and more studies should be conducted to determine the actual prevalence of these haemosporidian parasites among other bird species within NZG.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA