Native strains of Beauveria bassiana for the control of Rhipicephalus sanguineus sensu lato

Background Rhipicephalus sanguineus sensu lato ticks are widespread worldwide due to their adaptability to survive under different environmental conditions. They may act as vectors of a wide range of pathogens to humans and animals and their control is based on the use of chemical products on dogs and in the environment. Alternative control strategies, such as the use of entomopathogenic fungi as bio-control agents have also been investigated. The ability of native strains of Beauveria bassiana sensu lato in causing mortality in different tick species (e.g., Amblyomma cajennense and Rhipicephalus microplus) has been demonstrated. However, limited studies have assessed the use of B. bassiana for the control of R. sanguineus s.l. and none of them have employed native strains of this fungus. Here we investigated the pathogenicity of a native strain of B. bassiana (CD1123) against all developmental stages of R. sanguineus s.l.. Methods Batches of eggs, larvae, nymphs and adult ticks were immersed in a suspension of 107 conidia/ml of B. bassiana s.l., isolated from a R. sanguineus s.l. engorged female. All treatment and control groups were observed for 20 days, and the biological parameters (i.e., mortality, hatching, moulting percentage, pre-oviposition period, oviposition period and rate, eggs production efficiency, reproductive efficiency and fitness indexes) were assessed. Results The effect of the B. bassiana strain tested herein on eggs, larvae, nymphs and adults showed a significantly higher mortality than those of the control groups (p < 0.05) at 5 days post-infection. No infected eggs hatched and no infected larvae moulted. Only 15% of infected nymphs moulted into adults. All biological parameters of treated groups differed significantly (p < 0.001) from those of control groups. Conclusions This study demonstrates that a suspension containing 107 conidia/ml of a native B. bassiana strain is highly virulent towards all life-cycle developmental stages of R. sanguineus s.l. and may be of potential interest as a biological control agent against these ticks

Ocorrência de anticorpos anti-neospora caninum em cães dos municípios de Paulista e Amaraji, estado de Pernambuco, Brasil

A neosporose é uma doença causada pelo coccídio Neospora caninum que afeta uma grande variedade de animais silvestres e domésticos. Essa doença tem sido associada a aborto em bovinos em muitas partes do mundo e hoje é reconhecida como uma causa de perdas significativas para a indústria mundial de animais de produção. Estudos têm sido realizados para avaliar a prevalência de anticorpos anti-N. caninum em cães de muitos estados brasileiros. Até o momento, entretanto, não existe estudo relatando a ocorrência de anticorpos anti-N. caninum em cães no Estado de Pernambuco. Nesse contexto, objetivou-se com o presente estudo avaliar a ocorrência de anticorpos anti-N. caninum em dois municípios no Estado de Pernambuco. No total, 455 amostras de soro de cães, sendo 287 do município de Paulista (Região Metropolitana de Recife) e 168 do município de Amaraji (Zona da Mata), foram testadas pela reação deimunofluorescência indireta para detecção de anticorpos anti-N. caninum. Das 455 amostras testadas, 118 (25,9%; IC 95%, 21,9–30,2) foram positivas. As freqüências encontradas em Paulista e Amaraji foram 26,1% (IC 95%: 21,1–31,6) e 25,6% (IC 95%: 19,1–32,8), respectivamente. Conclui-se que os cães de Amaraji e Paulista encontram-se expostos à infecção por N. caninum, constituindo um potencial fator de risco para ocorrência de surtos de abortos em bovinos e outros ruminantes nesses municípios.Neosporosis is a disease caused by the coccidian parasite Neospora caninum that affects a great variety of domestic and wild animals. This disease has been associated with abortion in cattle in many parts of the word and today it is recognized a cause of significant losses to the worldwide livestock industry. Studies have been carried out to access the occurrence of antibodies to N. caninum in dogs from many Brazilian states. To date, however, there is no study reporting the occurrence of antibodies against N. caninum in dogs in the State of Pernambuco. In this context, the objective of this study was to access the occurrence of antibodies to N. caninum in two municipalities of Pernambuco. A total of 455 serum samples of dogs, being 287 from the municipality of Paulista (metropolitan region of Recife) and 168 from the municipality Amaraji(Atlantic Rainforest region), were tested by an immunofluorescence antibody reaction to detect antibodies to N. caninum. Out of the 455 samples tested, 118 (25.9%; IC 95%, 21.9–30.2) were positive. The seroprevalence rates found in Paulista and Amaraji were26.1% (IC 95%: 21.1–31.6) and 25.6% (IC 95%: 19.1 32.8), respectively. In conclusion, dogs from Amaraji and Paulista are exposed to N. caninum infection,constituting a potential risk factor for the occurrence of outbreaks of abortion in cattle and other ruminants in these municipalities.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPE

Heterodoxus spiniger (Enderlein, 1909) em cães domésticos (Canis familiaris, L. 1758) da cidade de Recife, Estado de Pernambuco, Brasil

In the city of Recife, Pernambuco state, northeastern Brazil, domestic dogs are usually infected by ectoparasites of both veterinary and public health importance. Heterodoxus spiniger is a common dog chewing louse, which is known as an intermediate host of Dipetalonema reconditum. Despite of its wide geographical diffusion in Brazil, Heterodoxus spiniger was only recently recorded in Pernambuco. The aim of this paper was to verify the infestations by Heterodoxus spiniger on dogs from Recife. Three hundred and ten dogs were examined and 11 of these were parasitized by Heterodoxus spiniger, corresponding to a prevalence rate of 3.5%. This indicates that Heterodoxus spiniger can be found on dogs from Recife, but in low prevalence.Na cidade de Recife, Estado de Pernambuco, nordeste do Brasil, os cães domésticos são freqüentemente infestados por ectoparasitos de interesse para medicina veterinária e para a saúde pública. Heterodoxus spiniger é um piolho mastigador comum em cães, apontado como hospedeiro intermediário de Dipetalonema reconditum. Apesar de sua ampla difusão geográfica no Brasil, apenas recentemente o piolho Heterodoxus spiniger foi registrado em Pernambuco. Neste sentido, o objetivo deste estudo foi verificar a presença de piolhos da referida espécie em cães de Recife. Dos 310 cães examinados, 11 estavam parasitados por Heterodoxus spiniger, correspondendo a uma taxa de prevalência de 3,5%. Este resultado indica que esta espécie de piolho mastigador pode ser encontrada em cães procedentes de Recife, porém com baixa prevalência

Clinical and hematological findings in Leishmania braziliensis-infected dogs from Pernambuco, Brazil Achados clínicos e hematológicos em cães infectados por Leishmania braziliensis de Pernambuco, Brasil

Abstract Canine cutaneous leishmaniasis by Leishmania braziliensis is a neglected, but widespread disease of dogs in South America. This paper describes clinical and hematological alterations in 17 L. braziliensis-infected dogs from Brazil. The most common hematological findings were thrombocytopenia (82.4%), anemia (70.6%), low packed cell volume (52.9%) and eosinophilia (41.2%). Twelve (70.6%) dogs displayed at least one evident physical alteration; 11 dogs (64.7%) presented skin lesions, four (23.5%) had weight loss and two (11.8%) onychogryphosis. L. braziliensis-infected dogs present clinical and hematological signs often observed in dogs infected by other pathogens. This indicates that veterinarians and public health workers should not consider the presence of non-specific clinical signs as diagnostic criteria for visceral leishmaniasis in dogs living endemic areas to avoid misdiagnosis and subsequent elimination of dogs infected by L. braziliensis. Keywords: Leishmania braziliensis, dogs, Pernambuco, Brazil. Resumo A leishmaniose cutânea canina causada por Leishmania braziliensis é uma doença negligenciada, mas disseminada entre cães na America do Sul. Este artigo descreve alterações clínicas e hematológicas em 17 cães infectados por L. braziliensis do Brasil. As alterações hematológicas mais comuns foram trombocitopenia (82,4%), anemia (70,6%), baixo valor de hematócrito (52,9%) e eosinofilia (41,2%). Doze (70,6%) cães apresentaram pelo menos uma alteração física; 11 (64,7%) apresentaram lesões cutâneas, quatro (23,5%) perda de peso e dois (11,8%) onicogrifose. Cães infectados por L. braziliensis apresentaram alterações clínicas e hematológicas inespecíficas que são comumente observadas em cães infectados por outros patógenos. Isso indica que veterinários e profissionais de saúde pública não deveriam considerar a presença de tais sinais clínicos como critério de diagnóstico para leishmaniose visceral em cães, em áreas endêmicas, no intuito de evitar um diagnóstico equivocado e a subsequente eliminação de cães infectados por L. braziliensis

Acaricidal effects of Beauveria bassiana in combination with Eucalyptus globulus essential oil against Dermanyssus gallinae

The poultry red mite, Dermanyssus gallinae, is the most economically damaging ectoparasite of laying hens worldwide. The disadvantages of using chemicals against this mite (i.e., environmental and food contamination and drug resistance) have spurred the interest of the scientific community in developing alternative methods for its control. Eucalyptus globulus essential oil (EgEO) and Beauveria bassiana (Bb) have the potential to be used as alternative approaches for D. gallinae control. These compounds have some limitations in their use: the acaricidal effect of EgEO is rapid, but short-lived, whilst that of Bb is delayed, but longlived. This study reports the effect of a native strain of Bb in combination with EgEO, against D. gallinae nymphs and adults. Batches of nymphs and adult mites (i.e., 360 individuals for each stage) for the treatment groups (TGs) were placed on paper soaked with a 0.1% tween 80 suspension of 109 conidia/ml of Bb (CIS) in combination with two different EgEO concentrations (i.e., 0.2% and 0.1%), whilst 720 control mites for each stage (CGs) were exposed to 0.1% tween 80 (CG1), to Bb 109 CIS (CG2), to 0.2% EgEO (CG3) and to 0.1% EgEO (CG4). A 100% mortality was recorded in adults at 9 days post infection (DPI) and at 10 DPI in nymphs, when using CIS in combination with 0.2% EgEO, but in CG2 at 12 DPI for adults and 14 DPI for nymphs. Used in combination with 0.2% EgEO, Bb displayed an earlier acaricidal effect towards both D. gallinae stages. The combination of B.bassiana 109 CIS and E. globulus essential oil at 0.2% might be a promising natural control method for use in a pest management strategy against mite infestations in poultry houses

Exposure to vector-borne pathogens in privately owned dogs living in different socioeconomic settings in Brazil

This survey was conducted in four Brazilian cities, from three federative units (Pernambuco, Minas Gerais, and Federal District), representing different socioeconomic settings, to determine the presence of antibodies to or antigens and DNA of selected pathogens in privately owned dogs. From January to April 2015, blood and serum samples were collected and assayed using different tests. In particular, antibodies to Anaplasma spp., Borrelia burgdorferi sensu lato, and Ehrlichia spp., and antigens of Dirofilaria immitis were detected using a rapid enzyme-linked immunosorbent assay, whereas antibodies to Babesia spp. were detected by an immunofluorescence antibody assay. Moreover, the presence of Leishmania DNA in blood samples was assessed by real-time polymerase chain reaction. Overall, 208 (69.3%) out of 300 dogs were positive for at least one tested pathogen (intended here as antibodies, antigen or DNA, as abovementioned), with 139 (66.8%) of them being positive to two or more pathogens. No dog presented antibodies to B. burgdorferi s.l., and D. immitis antigens were detected exclusively in dogs from Pernambuco. Among positive dogs, the most common clinical signs were lymphadenomegaly (45.2%), onychogryphosis (41.3%), dermatitis (34.1%), pale mucous membranes (19.7%), weight loss (14.9%), fever (12.5%), alopecia (11.1%), and lethargy (4.8%). Tick and flea infestations were recorded in 41.7% and 29.3% of the dogs, respectively, with 49 (16.3%) dogs being co-infested by both ticks and fleas. Most of the tick- and flea-infested dogs presented high level of infestation (>10 ticks and >20 fleas). The level of tick infestation varied significantly among federative units, being highest in Minas Gerais (68.0%), followed by Pernambuco (36.0%) and Federal District (21.0%). On the other hand, the level of flea infestation was higher in Pernambuco (50.0%), followed by Minas Gerais (29.0%) and Federal District (9.0%). The number of dog owners reporting the use of ectoparasiticides (on dogs and/or in the environment) varied significantly, ranging from 6.0% in Pernambuco to 60.0% in Federal District. This study reveals disparate results in terms of dog exposure to fleas and ticks in the studied communities, which may be related to factors such as the ownersâ\u80\u99 capability/willingness to afford the use of ectoparasiticides on their dogs and the dog's level of restriction. Further research is needed to establish the relationship between dog ownersâ\u80\u99 socioeconomic situation and the level of exposure to ectoparasites and their transmitted pathogens

Leishmania-FAST15: A rapid, sensitive and low-cost real-time PCR assay for the detection of Leishmania infantum and Leishmania braziliensis kinetoplast DNA in canine blood samples

We describe an improved real-time PCR assay (designated as “Leishmania-FAST15”) for the detection and quantification of Leishmania infantum and Leishmania braziliensis kinetoplast DNA minicircles in canine blood samples. The analytical sensitivity of this technique is 0.1 fg of DNA, which is equivalent to 0.002 parasite per reaction. This assay uses a small reaction volume (15 μl) and is rapid to perform, with the results being available in less than 34 min. This improved assay might also be suitable for detecting and quantifying L. infantum and L. braziliensis DNA in other tissues, such as bone marrow and lymph nodes

Influence of different storage conditions on the viability and virulence of Beauveria bassiana conidia infection suspension

Beauveria bassiana myco-insecticides/acaricides are usually formulated as conidia infection suspensions (CIS) in sterile distilled water plus 0.1% tween 80 (v/v) for field and laboratory applications. However, stress factors i.e., temperature, UV radiation, oxygenation, can over time compromise the conidial viability and virulence. The native strain of B. bassiana has been shown to be highly virulent against the poultry red mite Dermanyssus gallinae. With the aim of investigating the best storage conditions for extending the CIS shelf-life, viability and virulence of native B. bassiana CIS stored at ambient and refrigerated temperatures (i.e., 20±1 °C and 4±1 °C, respectively), with and without light and agitation, were assessed over a one year period. The viability of conidia was assessed monthly by quantitative plate counts of colony forming units (CFU)/ml on potato dextrose agar after incubation at 25°C for 4 days. The virulence of B. bassiana was evaluated towards D. gallinae five times in one year (i.e., at T0 and every 3 months of storage). Independently of light conditions and agitation, all CIS stored at 20±1 °C showed a reduction of about two logarithmic units of CFU/ml, starting from the 2nd month, which persisted until the 12th incubation month. CIS stored at 4±1°C showed a reduction of about one logarithmic unit of CFU/ml starting from the 7th month and remained unchanged until the end of the monitoring time. The highest mortality rate of D. gallinae was registered for CIS stored at 4±1°C, in the dark and without agitation. This study suggests that the viability of the spores during storage is only dependent on temperature, whereas the virulence of the fungus is influenced by temperature, light and agitation. Refrigerating CIS (i.e., 4±1 °C), with storage in the dark and without agitation seems to guarantee the best viability and performance against D. gallinae, thus it can be considered the most appropriate storage method

Clinical and hematological findings in Leishmania braziliensis-infected dogs from Pernambuco, Brazil Achados clínicos e hematológicos em cães infectados por Leishmania braziliensis de Pernambuco, Brasil

Canine cutaneous leishmaniasis by Leishmania braziliensis is a neglected, but widespread disease of dogs in South America. This paper describes clinical and hematological alterations in 17 L. braziliensis-infected dogs from Brazil. The most common hematological findings were thrombocytopenia (82.4%), anemia (70.6%), low packed cell volume (52.9%) and eosinophilia (41.2%). Twelve (70.6%) dogs displayed at least one evident physical alteration; 11 dogs (64.7%) presented skin lesions, four (23.5%) had weight loss and two (11.8%) onychogryphosis. L. braziliensis-infected dogs present clinical and hematological signs often observed in dogs infected by other pathogens. This indicates that veterinarians and public health workers should not consider the presence of non-specific clinical signs as diagnostic criteria for visceral leishmaniasis in dogs living endemic areas to avoid misdiagnosis and subsequent elimination of dogs infected by L. braziliensis.A leishmaniose cutânea canina causada por Leishmania braziliensis é uma doença negligenciada, mas disseminada entre cães na America do Sul. Este artigo descreve alterações clínicas e hematológicas em 17 cães infectados por L. braziliensis do Brasil. As alterações hematológicas mais comuns foram trombocitopenia (82,4%), anemia (70,6%), baixo valor de hematócrito (52,9%) e eosinofilia (41,2%). Doze (70,6%) cães apresentaram pelo menos uma alteração física; 11 (64,7%) apresentaram lesões cutâneas, quatro (23,5%) perda de peso e dois (11,8%) onicogrifose. Cães infectados por L. braziliensis apresentaram alterações clínicas e hematológicas inespecíficas que são comumente observadas em cães infectados por outros patógenos. Isso indica que veterinários e profissionais de saúde pública não deveriam considerar a presença de tais sinais clínicos como critério de diagnóstico para leishmaniose visceral em cães, em áreas endêmicas, no intuito de evitar um diagnóstico equivocado e a subsequente eliminação de cães infectados por L. braziliensis