RESUMO
The intermediate hosts of the French heartworm Angiostrongylus vasorum are aquatic and terrestrial gastropods. The present work is aimed at clarifying the sites of penetration and the migratory routes of A. vasorum in Biomphalaria glabrata snail tissues and evaluating their perilarval reaction with regard to the cellular composition and histological alterations involved in the gastropod response to infection. Biomphalaria glabrata snails were individually infected with 1000 first-stage larvae (L1) of A. vasorum each and killed at predetermined times after infection. Percutaneous infection occurred simultaneously with oral infection. Despite larval tropism to the fibromuscular tissue, some larvae were located in different tissues and organs. A perilarval reaction was observed around the larvae in a fibromuscular layer, appearing later around the larvae located in the viscera. The number of hemocytes surrounding the larvae increased gradually, forming a pregranuloma. Larval death and degeneration were not observed. No defined migratory pattern occurred, and larval development was apparently not associated with particular tissues or organs. In addition, the infection by A. vasorum induces a systemic mobilization of hemocytes in perilarval reaction.
RESUMO
Anthelminthic resistant populations of Haemonchus contortus are a major problem in sheep rearing, but plant extracts may offer viable alternative treatments. In our preliminary studies, Piptadenia viridiflora was frequently selected by sheep grazing in the Cerrado. The present research evaluated its in vitro and in vivo anthelmintic activity. The HPLC chromatograms of P. viridiflora aqueous extract (AE) and ethanolic extract (EE) showed the presence of flavonoids. The total condensed tannin (proanthocyanidin) was 0.2 and 1.01% in AE and EE, respectively. In an egg hatching inhibition (EHI) test, the LC90 of AE was 2.4mg/mL, and, of EE, was 2.1mg/mL. After tannin extraction, higher EHI and lower LC90 were observed. In a larval development inhibition test, the LC90 of AE was 13.66mg/g of fecal culture. The highest dose of AE administered to mice (203.0mg/kg bw) was well tolerated, suggesting low toxicity. In vivo, AE was orally administered to lambs at 283mg/kg bw, and, at weeks one, two, and three post-treatment, the mean fecal egg count (FEC) was significantly lower than in untreated lambs (P<0.05). Blood parameters were normal and similar in untreated and treated sheep. For all lamb groups, the mean total serum protein was significantly higher at week two post-treatment than at other evaluated periods (P<0.05). Piptadenia viridiflora extracts had low condensed tannin content and exhibited high anthelminthic efficacy in vitro and significantly reduced FEC. Tannins were not shown to be the principal components affecting EHI, hence it is necessary to isolate and characterize the principal active P. viridiflora compounds, and to assess their possible synergism.
Assuntos
Anti-Helmínticos/uso terapêutico , Fabaceae/química , Hemoncose/veterinária , Haemonchus/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Doenças dos Ovinos/parasitologia , Animais , Anti-Helmínticos/efeitos adversos , Anti-Helmínticos/química , Hemoncose/tratamento farmacológico , Ivermectina/uso terapêutico , Levamisol/uso terapêutico , Camundongos , Óvulo/efeitos dos fármacos , Extratos Vegetais/efeitos adversos , Extratos Vegetais/química , Folhas de Planta/química , Ovinos , Doenças dos Ovinos/tratamento farmacológico , Testes de ToxicidadeRESUMO
Angiostrongylus vasorum is a parasitic nematode that infects the heart and pulmonary artery and its branches of domestic and wild canids. The parasite can use several species of terrestrial and aquatic molluscs as intermediate hosts, although susceptibility varies. Pomacea canaliculata is a mollusc found in lakes, swamps and rivers in South America. In this study, we evaluated the susceptibility, parasite growth, oviposition and larval development of 282 P. canaliculata infected with 500 A. vasorum first-instar larvae (L1). From day 5 post-infection (pi) to day 30 pi, seven specimens per day were sacrificed to recover the larval instars. We compared 50 egg masses from infected and uninfected molluscs to determine the number of eggs per clutch, the hatching rate and the growth of the molluscs. The percentage of recovered larvae ranged from 39.17% to 67.5%. First-stage larvae (L1) were found until day 19 pi, second-stage larvae (L2) were found from days 11 to 25 pi, and third-stage larvae (L3) were recovered only after day 19 pi. Infected snails exhibited the most eggs during spawning, although the rate of hatching and shell size were lower in the infected snails compared with controls. This is the first report of an experimental infection of P. canaliculata with A. vasorum, and the results confirm the non-specificity of the nematode in relation to the intermediate host and indicate the importance of epidemiological surveys of this parasite and mollusc.
Assuntos
Angiostrongylus/crescimento & desenvolvimento , Caramujos/parasitologia , Animais , Feminino , Água Doce/parasitologia , Larva/crescimento & desenvolvimento , MasculinoRESUMO
Angiostrongylus vasorum é um nematóide cardio-pulmonar de cães domésticos e canídeos selvagem, que pode causar sinais clínicos e patológicos, tais como: pneumonia, intolerância ao exercício, perda de peso, anemia, tosse, insuficiência cardíaca, fibrose pulmonar e morte. O diagnóstico padrão ouro de angiostrongilose é o de teste de Baermann, que é baseado na presença de larvas de primeiro estádio nas fezes de animais infectados. A lavagem broncoalveolar (LBA), permite a recuperação das células e outros elementos dos pulmões, e é usado no diagnóstico de avaliação de doenças respiratórias em seres humanos e animais. O objetivo deste estudo foi avaliar o LBA como uma ferramenta de diagnóstico nas fases aguda e crônica da angiostrongilíase canina. A técnica LAB foi realizada em sete animais infectados experimentalmente com A. vasorum e cinco animais não infectados, definido como o grupo de controle nos dias: 0, 30, 60, 90, 120, 180, 240 e 330. Os animais permaneceram em jejum de sólidos durante 12 horas antes da terapia com uma s
RESUMO
Angiostrongylus vasorum é um nematóide cardio-pulmonar de cães domésticos e canídeos selvagem, que pode causar sinais clínicos e patológicos, tais como: pneumonia, intolerância ao exercício, perda de peso, anemia, tosse, insuficiência cardíaca, fibrose pulmonar e morte. O diagnóstico padrão ouro de angiostrongilose é o de teste de Baermann, que é baseado na presença de larvas de primeiro estádio nas fezes de animais infectados. A lavagem broncoalveolar (LBA), permite a recuperação das células e outros elementos dos pulmões, e é usado no diagnóstico de avaliação de doenças respiratórias em seres humanos e animais. O objetivo deste estudo foi avaliar o LBA como uma ferramenta de diagnóstico nas fases aguda e crônica da angiostrongilíase canina. A técnica LAB foi realizada em sete animais infectados experimentalmente com A. vasorum e cinco animais não infectados, definido como o grupo de controle nos dias: 0, 30, 60, 90, 120, 180, 240 e 330. Os animais permaneceram em jejum de sólidos durante 12 horas antes da terapia com uma s
RESUMO
This note describes the sudden death of a dog by the rupture of the thoracic aorta caused by the presence of Angiostrongylus vasorum. A female mongrel canine with a history of weight loss and exhaustion died two hours after clinical examination. At necropsy, performed one hour after death, showed the presence of clotted blood in the thoracic cavity. Haemothorax was diagnosed. The thoracic aorta wall was thin, congested and an abnormal hole in the wall was detected approximately 0.5 cm from the entrance to the diaphragm. From clotted blood collected from the thoracic cavity, 224 first stage larvae (L1) and 15 adults of Angiostrongylus vasorum were recovered alive. Also, from a blood clot found in the aorta, four adult females and 47 L1 larvae were recovered alive. Possibly, this parasite was responsible for the aortic rupture and death of the animal.
Assuntos
Aorta Torácica/parasitologia , Ruptura Aórtica/veterinária , Morte Súbita/veterinária , Doenças do Cão/parasitologia , Infecções por Strongylida/veterinária , Angiostrongylus/classificação , Angiostrongylus/isolamento & purificação , Animais , Aorta Torácica/patologia , Ruptura Aórtica/parasitologia , Autopsia/veterinária , Morte Súbita/etiologia , Diagnóstico Diferencial , Doenças do Cão/diagnóstico , Doenças do Cão/patologia , Cães , Evolução Fatal , Fezes/parasitologia , Feminino , Larva , Masculino , Infecções por Strongylida/complicações , Infecções por Strongylida/diagnósticoRESUMO
The susceptibility and suitability of Omalonyx matheroni as an intermediate host of Angiostrongylus vasorum and the characteristics of larval recovery and development were investigated. Mollusks were infected, and from the 3rd to the 25th day after infection, larvae were recovered from groups of 50 individuals. The first observation of L2 was on the 5th day, and the first observation of L3 was on the 10th day. From the 22nd day on, all larvae were at the L3 stadium. Larval recovery varied from 78.2% to 95.2%. We found larval development to be faster in O. matheroni than in Biomphalaria glabrata. Our findings indicate that this mollusk is highly susceptible to A. vasorum. Infective L3 were orally inoculated into a dog, and the prepatent period was 39 days. This is the first study to focus on O. matheroni as an intermediate host of A. vasorum.
RESUMO
Angiostrongylus vasorum is a nematode that parasitizes domestic dogs and wild canids. We compared the predatory capacity of isolates from the predatory fungi Duddingtonia flagrans (AC001), Monacrosporium thaumasium (NF34), Monacrosporium sinense (SF53) and Arthrobotrys robusta (I31) on first-stage larvae (L1) of A. vasorum under laboratory conditions. L1 A. vasorum were plated on 2% water-agar (WA) Petri dishes marked into 4 mm diameter fields with the four grown isolates and a control without fungus. Plates of treated groups contained each 1000 L1 A. vasorum and 1000 conidia of the fungal isolates AC001, NF34, SF53 and I31 on 2% WA. Plates of the control group (without fungus) contained only 1000 L1 A. vasorum on 2% WA. Ten random fields (4 mm diameter) were examined per plate of treated and control groups, every 24 h for 7 days. Nematophagous fungi were not observed in the control group during the experiment. There was no variation in the predatory capacity among the tested fungal isolates (P>0.05) during the 7 days of the experiment. There was a significant reduction (P < 0.05) of 80.3%, 74.5%, 74.2% and 71.8% in the means of A. vasorum L1 recovered from treatments with isolates AC001, NF34, SF53 and I31, respectively, compared to the control without fungi. In this study, the four isolates of predatory fungi were efficient in the in vitro capture and destruction of A. vasorum L1, confirming previous work on the efficiency of nematophagous fungi in the control of nematode parasites of dogs and as a possible alternative method of biological control.
Assuntos
Angiostrongylus/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Nematoides/crescimento & desenvolvimento , Infecções por Nematoides/prevenção & controle , Angiostrongylus/microbiologia , Animais , Cães , Interações Hospedeiro-Parasita , Larva/microbiologia , Nematoides/microbiologia , Infecções por Nematoides/veterinária , Contagem de Ovos de Parasitas , Controle Biológico de Vetores/métodos , Especificidade da EspécieRESUMO
Experimental infections of Lymnaea columella with Fasciola hepatica were carried out to test the effect of sympatric and allopatric combinations between parasite and host, by using snails and flukes from southern and south-eastern Brazil. Four groups of 50 snails were infected with four miracidia per snail: two groups in sympatric and two groups in allopatric combinations. Sympatric combinations between parasite and host were more efficient than allopatric ones when snails from Itajubá were used, but the opposite was observed in infections involving snails from Pelotas. The sympatric association between L. columella and F. hepatica from Itajubá was significantly higher than in the other combinations. We concluded that the host-parasite relationship between L. columnella and F. hepatica may vary according to the geographical origin of the snails and flukes involved.
Assuntos
Fasciola hepatica/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Lymnaea/parasitologia , Animais , Brasil , Interações Hospedeiro-Parasita , Estágios do Ciclo de Vida , Dinâmica PopulacionalRESUMO
Bronchoalveolar lavage (BAL) is a procedure that retrieves cells and other elements from the lungs for evaluation, which helps in the diagnosis of many pulmonary diseases. The aims of this work were to perform this procedure in dogs in the acute and chronic phases of an Angiostrongylus vasorum infection for cytological analysis and to evaluate the potential of this technique as a diagnostic method for this lung-heart worm. The BAL procedure was performed through the use of an endotracheal tube on seven A. vasorum infected dogs and on five non-infected dogs lined as a control group. Sixty days post-infection (dpi) active and live larvae were retrieved from the bronchoalveolar fluid (BALF) of all infected dogs. Furthermore, in one animal it was possible to retrieve larvae in its BALF before the pre-patent period. This work reports that the A. vasorum infection resulted in an increase of relative neutrophils and eosinophils counts. In contrast, there was a significant decrease in the alveolar macrophage relative count in infected animals from 60 to 330 dpi. This study shows that the BAL is an accurate technique for the diagnosis of canine angiostrongylosis. Moreover, the technique allows us to retrieve cells and other elements that line the lung surface for cytological evaluation, which provides information about inflammatory diseases, and the diagnosis and prognosis of pulmonary parasites such as A. vasorum.